1
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The CC Genotype of Insulin-Induced Gene 2 rs7566605 Is a Protective Factor of Hypercholesteremia Susceptible to Mild Cognitive Impairment, Especially to the Executive Function of Patients with Type 2 Diabetes Mellitus. BIOMED RESEARCH INTERNATIONAL 2021; 2020:4935831. [PMID: 32596317 PMCID: PMC7303749 DOI: 10.1155/2020/4935831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 04/04/2020] [Accepted: 05/28/2020] [Indexed: 01/05/2023]
Abstract
Methods 233 T2DM patients with MCI or without MCI were recruited. Baseline data and genotype frequency were compared between MCI and non-MCI groups. Demographic parameters and neuropsychological tests results were analyzed among patients with different genotypes. Further correlation and regression analysis were conducted to find the association between cognition and cholesterol. Results Despite no significant statistical difference was detected, we observed higher levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) in patients with MCI than those without MCI. In addition, we observed higher TC and LDL levels in patients with GG or GC genotypes than those with CC genotype (P < 0.001, P = 0.004, or P < 0.001, P = 0.002). Interestingly, increased MoCA and decreased TMTB scores were found in patients with CC genotype, compared to those with GG or CG genotype (P = 0.009, P = 0.024, or P = 0.005, P = 0.109). Moreover, partial correlation (P = 0.030 and P = 0.004, respectively) and multiple linear regression (P = 0.030 and P = 0.005, respectively) showed that TC and LDL levels are associated with the TMTB score, indicating the executive function. Conclusions CC genotype of INSIG-2 rs7566605 may be a protective factor of hypercholesteremia susceptible to MCI, especially to the executive function of T2DM. This trial is registered with ChiCTROCC15006060.
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2
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Prakash J, Mittal B, Apurva S, Shally A, Pranjal S, Neena S. Common Genetic Variant of insig2 Gene rs7566605 Polymorphism Is Associated with Severe Obesity in North India. IRANIAN BIOMEDICAL JOURNAL 2017; 21:261-9. [PMID: 28160769 PMCID: PMC5459941 DOI: 10.18869/acadpub.ibj.21.4.261] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Background: Obesity is a very common disorder resulting from an imbalance between food intake and energy expenditure, and it has a substantial impact on the development of chronic diseases. The aim of this study was to examine the association of INSIG2 (rs7566605) gene polymorphism with obesity and obesity associated phenotypes in North Indian subjects. Methods: The variants were investigated for association in 642 obese and non-obese individuals. The genotyping of INSIG2 (rs7566605) single nucleotide polymorphism was analyzed by the TaqMan allelic discrimination protocol. Results: A significant association was observed for INSIG2 (rs7566605) single nucleotide polymorphism with obesity and obesity-related phenotypes. Furthermore, a significant relationship was found between the rs7566605 and insulin, homeostasis model of assessment-insulin resistance, the percentage of body fat, fat mass, leptin, and adiponectin. Conclusion: The present study observed significant association between INSIG2 (rs7566605) single nucleotide polymorphism and obesity, as well as obesity-associated phenotypes in North Indian population.
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Affiliation(s)
- Jai Prakash
- Department of Physiology, King George’s Medical University, Lucknow, Uttar Pradesh, India.,2Department of Pediatrics, King George’s Medical University, Lucknow, Uttar Pradesh, India
| | - Balraj Mittal
- 3Department of Genetics, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, U.P., India
| | - Srivastava Apurva
- Department of Physiology, King George’s Medical University, Lucknow, Uttar Pradesh, India
| | - Awasthi Shally
- 2Department of Pediatrics, King George’s Medical University, Lucknow, Uttar Pradesh, India
| | - Srivastava Pranjal
- Darbhanga Medical College and Hospital Near Karpuri Chowk Benta Laheriasarai Darbhanga Bihar 846003, India
| | - Srivastava Neena
- Department of Physiology, King George’s Medical University, Lucknow, Uttar Pradesh, India
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3
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Koskinen S, Kampman O, Solismaa A, Lyytikäinen LP, Seppälä N, Viikki M, Hämäläinen M, Moilanen E, Mononen N, Lehtimäki T, Leinonen E. INSIG2 polymorphism and weight gain, dyslipidemia and serum adiponectin in Finnish patients with schizophrenia treated with clozapine. Pharmacogenomics 2016; 17:1987-1997. [DOI: 10.2217/pgs-2016-0117] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: To investigate INSIG2's association with obesity, weight change and serum lipid profile during clozapine treatment. Materials & methods: Subjects with schizophrenia (n = 190) were genotyped, identifying seven SNPs. Genetic risk scores (GRSs) were calculated to adiponectin, high-density lipoprotein cholesterol, triglycerides and weight gain. Results: In the model for weight gain, SNPs rs12151787, rs17047733 and rs10490626 were selected. Explanatory variables were BMI (p = 5.05 × 10-5), age (p = 0.003) and GRS (p = 2.81 × 10-5, p = 0.0002 after permutation). No GRS resulted for adiponectin or high-density lipoprotein cholesterol. Rs2161829 and rs10490620 were selected for triglycerides; this GRS was insignificant after permutation. Conclusion: INSIG2 plays a role in weight gain and obesity during clozapine treatment.
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Affiliation(s)
- Suvi Koskinen
- School of Medicine, University of Tampere, 33014 Tampere, Finland
| | - Olli Kampman
- School of Medicine, University of Tampere, 33014 Tampere, Finland
- Department of Psychiatry, Seinäjoki Hospital District, Seinäjoki, Finland
| | - Anssi Solismaa
- School of Medicine, University of Tampere, 33014 Tampere, Finland
- Department of Psychiatry, Seinäjoki Hospital District, Seinäjoki, Finland
| | - Leo-Pekka Lyytikäinen
- School of Medicine, University of Tampere, 33014 Tampere, Finland
- University of Tampere, School of Medicine, Department of Clinical Chemistry and Fimlab Laboratories, Tampere, Finland
| | - Niko Seppälä
- Department of Psychiatry, Tampere University Hospital, Tampere, Finland
| | - Merja Viikki
- School of Medicine, University of Tampere, 33014 Tampere, Finland
- Tampere Mental Health Centre, Tampere, Finland
| | - Mari Hämäläinen
- The Immunopharmacology Research Group, School of Medicine & Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Eeva Moilanen
- The Immunopharmacology Research Group, School of Medicine & Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Nina Mononen
- University of Tampere, School of Medicine, Department of Clinical Chemistry and Fimlab Laboratories, Tampere, Finland
| | - Terho Lehtimäki
- School of Medicine, University of Tampere, 33014 Tampere, Finland
- University of Tampere, School of Medicine, Department of Clinical Chemistry and Fimlab Laboratories, Tampere, Finland
| | - Esa Leinonen
- School of Medicine, University of Tampere, 33014 Tampere, Finland
- Department of Psychiatry, Tampere University Hospital, Tampere, Finland
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4
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Tumour biology of obesity-related cancers: understanding the molecular concept for better diagnosis and treatment. Tumour Biol 2016; 37:14363-14380. [PMID: 27623943 DOI: 10.1007/s13277-016-5357-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 09/07/2016] [Indexed: 12/18/2022] Open
Abstract
Obesity continues to be a major global problem. Various cancers are related to obesity and proper understanding of their aetiology, especially their molecular tumour biology is important for early diagnosis and better treatment. Genes play an important role in the development of obesity. Few genes such as leptin, leptin receptor encoded by the db (diabetes), pro-opiomelanocortin, AgRP and NPY and melanocortin-4 receptors and insulin-induced gene 2 were linked to obesity. MicroRNAs control gene expression via mRNA degradation and protein translation inhibition and influence cell differentiation, cell growth and cell death. Overexpression of miR-143 inhibits tumour growth by suppressing B cell lymphoma 2, extracellular signal-regulated kinase-5 activities and KRAS oncogene. Cancers of the breast, uterus, renal, thyroid and liver are also related to obesity. Any disturbance in the production of sex hormones and insulin, leads to distortion in the balance between cell proliferation, differentiation and apoptosis. The possible mechanism linking obesity to cancer involves alteration in the level of adipokines and sex hormones. These mediators act as biomarkers for cancer progression and act as targets for cancer therapy and prevention. Interestingly, many anti-cancerous drugs are also beneficial in treating obesity and vice versa. We also reviewed the possible link in the mechanism of few drugs which act both on cancer and obesity. The present review may be important for molecular biologists, oncologists and clinicians treating cancers and also pave the way for better therapeutic options.
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5
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Kaulfers AM, Deka R, Dolan L, Martin LJ. Association of INSIG2 polymorphism with overweight and LDL in children. PLoS One 2015; 10:e0116340. [PMID: 25607990 PMCID: PMC4301876 DOI: 10.1371/journal.pone.0116340] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 12/08/2014] [Indexed: 11/19/2022] Open
Abstract
Background Dyslipidemia and overweight are common issues in children. Identifying genetic markers of risk could lead to targeted interventions. A polymorphism of SNP rs7566605 near insulin-induced gene 2 (INSIG2) has been identified as a strong candidate gene for obesity, through its feedback control of lipid synthesis. Objective To identify polymorphisms in INSIG2 which are associated with overweight (BMI ≥ 85% for age) and dyslipidemia in children. Hypothesis: The C allele of rs7566605 would be significantly associated with BMI and LDL. Design/Methods We genotyped 15 SNPs in/near INSIG2 in 1,058 healthy children (53% non-Hispanic white (NHW), 37% overweight) participating in a school based study. Genotype was compared with BMI and lipid markers, adjusting for age, gender, and puberty. Results We found a significant association between the SNP rs12464355 and LDL in NHW children, p < 0.001. The G allele is protective (lower LDL). A different SNP was associated with overweight in NHW: rs17047757. SNP rs7566605 was not associated with overweight or lipid levels. Conclusions We identified novel genetic associations between INSIG2 and both overweight and LDL in NHW children. Polymorphisms in INSIG2 may be important in the development of obesity through its effects on lipid regulation.
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Affiliation(s)
- Anne-Marie Kaulfers
- Division of Pediatric Endocrinology, University of South Alabama, Mobile, Alabama, United States of America
- * E-mail:
| | - Ranjan Deka
- Department of Environmental Health, University of Cincinnati School of Medicine, Cincinnati, Ohio, United States of America
| | - Lawrence Dolan
- Division of Endocrinology, Cincinnati Children’s Hospital Medical Center and University of Cincinnati School of Medicine, Cincinnati, Ohio, United States of America
| | - Lisa J. Martin
- Divisions of Biostatistics and Epidemiology, Division of Human Genetics, Cincinnati Children’s Hospital Medical Center and University of Cincinnati School of Medicine, Cincinnati, Ohio, United States of America
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6
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Liu FH, Song JY, Zhang YN, Ma J, Wang HJ. Gender-Specific Effect of -102G>A Polymorphism in Insulin Induced Gene 2 on Obesity in Chinese Children. Int J Endocrinol 2015; 2015:872506. [PMID: 26161092 PMCID: PMC4487926 DOI: 10.1155/2015/872506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Revised: 05/25/2015] [Accepted: 06/04/2015] [Indexed: 11/17/2022] Open
Abstract
Background. Insulin induced gene 2 (INSIG2) encodes a protein that has a biological effect on regulation of adipocyte metabolism and body weight. This study aimed to investigate the association of INSIG2 gene -102G>A polymorphism with obesity related phenotypes in Chinese children and test gender-specific effects. Methods. The 2,030 independent individuals aged from 7 to 18 years, including 705 obese cases and 1,325 nonobese controls, were recruited from local schools. We measured the obesity-related phenotypes and detected the serum lipids. We genotype -102G>A polymorphism by using the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Results. In all individuals, we found that the GG/GA genotype of INSIG2 -102G>A polymorphism was associated with risk of severe obesity (OR = 1.62, 95% CI: 1.11-2.36, and P = 0.012) under the dominant model. The association with severe obesity existed only in boys (OR = 1.91, 95% CI: 1.15-3.17, P = 0.012). The GG/GA genotype of -102G>A polymorphism was also associated with higher waist circumference (β = 2.61 cm, P = 0.031) in boys. No similar association was found in girls. The polymorphism was not associated with other obesity-related phenotypes, neither in all individuals nor in gender-specific population. Conclusions. This study identified a gender-specific effect of INSIG2 -102G>A polymorphism on risk of severe obesity and waist circumference in Chinese boys.
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Affiliation(s)
- Fang-Hong Liu
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China
| | - Jie-Yun Song
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China
| | - Yi-Ning Zhang
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China
| | - Jun Ma
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China
- *Jun Ma: and
| | - Hai-Jun Wang
- Institute of Child and Adolescent Health, School of Public Health, Peking University, Beijing 100191, China
- *Hai-Jun Wang:
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7
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The gene-gene interaction of INSIG-SCAP-SREBP pathway on the risk of obesity in Chinese children. BIOMED RESEARCH INTERNATIONAL 2014; 2014:538564. [PMID: 25028659 PMCID: PMC4083216 DOI: 10.1155/2014/538564] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 05/26/2014] [Indexed: 11/20/2022]
Abstract
Background. Childhood obesity has become a global public health problem in recent years. This study aimed to explore the association of genetic variants in INSIG-SCAP-SREBP pathway with obesity in Chinese children. Methods. A case-control study was conducted, including 705 obese cases and 1,325 nonobese controls. We genotyped 15 single nucleotide polymorphisms (SNPs) of five genes in INSIG-SCAP-SREBP pathway, including insulin induced gene 1 (INSIG1), insulin induced gene 2 (INSIG2), SREBP cleavage-activating protein gene (SCAP), sterol regulatory element binding protein gene 1 (SREBP1), and sterol regulatory element binding protein gene 2 (SREBP2). We used generalized multifactor dimensionality reduction (GMDR) and logistic regression to investigate gene-gene interactions. Results. Single polymorphism analyses showed that SCAP rs12487736 and rs12490383 were nominally associated with obesity. We identified a 3-locus interaction on obesity in GMDR analyses (P = 0.001), involving 3 genetic variants of INSIG2, SCAP, and SREBP2. The individuals in high-risk group of the 3-locus combinations had a 79.9% increased risk of obesity compared with those in low-risk group (OR = 1.799, 95% CI: 1.475–2.193, P = 6.61 × 10−9). Conclusion. We identified interaction of three genes in INSIG-SCAP-SREBP pathway on risk of obesity, revealing that these genes affect obesity more likely through a complex interaction pattern than single gene effect.
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8
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Popadic Gacesa JZ, Secher NH, Momcilovic M, Grujic NG. Association between intramuscular fat in the arm following arm training andINSIG2. Scand J Med Sci Sports 2013; 24:907-12. [DOI: 10.1111/sms.12102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2013] [Indexed: 12/25/2022]
Affiliation(s)
- J. Z. Popadic Gacesa
- Department of Physiology; Medical School; University of Novi Sad; Novi Sad Serbia
| | - N. H. Secher
- The Copenhagen Muscle Research Center; Department of Anesthesiology; Rigshospitalet; University of Copenhagen; Copenhagen Denmark
| | - M. Momcilovic
- Department of Biochemistry; Medical School; University of Novi Sad; Novi Sad Serbia
| | - N. G. Grujic
- Department of Physiology; Medical School; University of Novi Sad; Novi Sad Serbia
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9
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Baylin A, Deka R, Tuitele J, Viali S, Weeks DE, McGarvey ST. INSIG2 variants, dietary patterns and metabolic risk in Samoa. Eur J Clin Nutr 2013; 67:101-7. [PMID: 22968099 PMCID: PMC3634362 DOI: 10.1038/ejcn.2012.124] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 08/16/2012] [Accepted: 08/18/2012] [Indexed: 12/11/2022]
Abstract
BACKGROUND/OBJECTIVES Association of insulin-induced gene 2 (INSIG2) variants with obesity has been confirmed in several but not all follow-up studies. Differences in environmental factors across populations may mask some genetic associations and therefore gene-environment interactions should be explored. We hypothesized that the association between dietary patterns and components of the metabolic syndrome could be modified by INSIG2 variants. SUBJECTS/METHODS We conducted a longitudinal study of adiposity and cardiovascular disease risk among 427 and 290 adults from Samoa and American Samoa (1990-1995). Principal component analysis on food items from a validated food frequency questionnaire was used to identify neotraditional and modern dietary patterns. We explored gene-dietary pattern interactions with the INSIG2 variants rs9308762 and rs7566605. RESULTS Results for American Samoans were mostly nonsignificant. In Samoa, the neotraditional dietary pattern was associated with lower triglycerides, body mass index (BMI), waist circumference, systolic and diastolic blood pressure and fasting glucose (all P-for-trend<0.05). The modern pattern was significantly associated with higher triglycerides, BMI, waist circumference and lower high-density lipoprotein-cholesterol (all P-for-trend<0.05). A significant interaction for triglycerides was found between the modern pattern and the rs9308762 polymorphism (P=0.04). Those from Samoa consuming the modern pattern have higher triglycerides if they are homozygous for the rs9308762 C allele. CONCLUSIONS The common INSIG2 variant rs9308762 was associated with poorer metabolic control and a greater sensitivity of trigylcerides to a modern dietary pattern. Environmental factors need to be taken into account when assessing genetic associations across and within populations.
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Affiliation(s)
- A Baylin
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA.
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10
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The challenges for molecular nutrition research 1: linking genotype to healthy nutrition. GENES AND NUTRITION 2011; 3:41-9. [PMID: 18850186 DOI: 10.1007/s12263-008-0086-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Nutrition science finds itself at a major crossroad. On the one hand we can continue the current path, which has resulted in some substantial advances, but also many conflicting messages which impair the trust of the general population, especially those who are motivated to improve their health through diet. The other road is uncharted and is being built over the many exciting new developments in life sciences. This new era of nutrition recognizes the complex relation between the health of the individual, its genome, and the life-long dietary exposure, and has lead to the realisation that nutrition is essentially a gene-environment interaction science. This review on the relation between genotype, diet and health is the first of a series dealing with the major challenges in molecular nutrition, analyzing the foundations of nutrition research. With the unravelling of the human genome and the linking of its variability to a multitude of phenotypes from "healthy" to an enormously complex range of predispositions, the dietary modulation of these propensities has become an area of active research. Classical genetic approaches applied so far in medical genetics have steered away from incorporating dietary effects in their models and paradoxically, most genetic studies analyzing diet-associated phenotypes and diseases simply ignore diet. Yet, a modest but increasing number of studies are accounting for diet as a modulator of genetic associations. These range from observational cohorts to intervention studies with prospectively selected genotypes. New statistical and bioinformatics approaches are becoming available to aid in design and evaluation of these studies. This review discusses the various approaches used and provides concrete recommendations for future research.
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11
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Population sequencing of two endocannabinoid metabolic genes identifies rare and common regulatory variants associated with extreme obesity and metabolite level. Genome Biol 2010; 11:R118. [PMID: 21118518 PMCID: PMC3156957 DOI: 10.1186/gb-2010-11-11-r118] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2010] [Revised: 08/28/2010] [Accepted: 11/30/2010] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Targeted re-sequencing of candidate genes in individuals at the extremes of a quantitative phenotype distribution is a method of choice to gain information on the contribution of rare variants to disease susceptibility. The endocannabinoid system mediates signaling in the brain and peripheral tissues involved in the regulation of energy balance, is highly active in obese patients, and represents a strong candidate pathway to examine for genetic association with body mass index (BMI). RESULTS We sequenced two intervals (covering 188 kb) encoding the endocannabinoid metabolic enzymes fatty-acid amide hydrolase (FAAH) and monoglyceride lipase (MGLL) in 147 normal controls and 142 extremely obese cases. After applying quality filters, we called 1,393 high quality single nucleotide variants, 55% of which are rare, and 143 indels. Using single marker tests and collapsed marker tests, we identified four intervals associated with BMI: the FAAH promoter, the MGLL promoter, MGLL intron 2, and MGLL intron 3. Two of these intervals are composed of rare variants and the majority of the associated variants are located in promoter sequences or in predicted transcriptional enhancers, suggesting a regulatory role. The set of rare variants in the FAAH promoter associated with BMI is also associated with increased level of FAAH substrate anandamide, further implicating a functional role in obesity. CONCLUSIONS Our study, which is one of the first reports of a sequence-based association study using next-generation sequencing of candidate genes, provides insights into study design and analysis approaches and demonstrates the importance of examining regulatory elements rather than exclusively focusing on exon sequences.
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12
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Campa D, Hüsing A, McKay JD, Sinilnikova O, Vogel U, Tjønneland A, Overvad K, Stegger J, Clavel-Chapelon F, Chabbert-Buffet N, Fagherazzi G, Trichopoulou A, Zylis D, Oustoglou E, Rohrmann S, Teucher B, Fisher E, Boeing H, Masala G, Krogh V, Sacerdote C, Panico S, Tumino R, Onland-Moret NC, van Gils CH, Bueno-de-Mesquita HB, Lund E, Chirlaque MD, Sala N, Quirós JR, Ardanaz E, Amiano P, Molina-Montes E, Hallmans G, Lenner P, Travis RC, Key TJ, Wareham N, Khaw KT, Rinaldi S, Slimani N, Chajes V, Siddiq A, Riboli E, Kaaks R, Canzian F. The INSIG2 rs7566605 polymorphism is not associated with body mass index and breast cancer risk. BMC Cancer 2010; 10:563. [PMID: 20955599 PMCID: PMC2965729 DOI: 10.1186/1471-2407-10-563] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 10/18/2010] [Indexed: 01/12/2023] Open
Abstract
Background The single nucleotide polymorphism rs7566605, located in the promoter of the INSIG2 gene, has been the subject of a strong scientific effort aimed to elucidate its possible association with body mass index (BMI). The first report showing that rs7566605 could be associated with body fatness was a genome-wide association study (GWAS) which used BMI as the primary phenotype. Many follow-up studies sought to validate the association of rs7566605 with various markers of obesity, with several publications reporting inconsistent findings. BMI is considered to be one of the measures of choice to evaluate body fatness and there is evidence that body fatness is related with an increased risk of breast cancer (BC). Methods we tested in a large-scale association study (3,973 women, including 1,269 invasive BC cases and 2,194 controls), nested within the EPIC cohort, the involvement of rs7566605 as predictor of BMI and BC risk. Results and Conclusions In this study we were not able to find any statistically significant association between this SNP and BMI, nor did we find any significant association between the SNP and an increased risk of breast cancer overall and by subgroups of age, or menopausal status.
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Affiliation(s)
- Daniele Campa
- German Cancer Research Center (DKFZ), Heidelberg, Germany
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13
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Do R, Bailey SD, Paré G, Montpetit A, Desbiens K, Hudson TJ, Yusuf S, Bouchard C, Gaudet D, Pérusse L, Anand S, Vohl MC, Pastinen T, Engert JC. Fine Mapping of the Insulin-Induced Gene 2 Identifies a Variant Associated With LDL Cholesterol and Total Apolipoprotein B Levels. ACTA ACUST UNITED AC 2010; 3:454-61. [DOI: 10.1161/circgenetics.109.917039] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Background—
In a whole-genome scan, a single nucleotide polymorphism (SNP) (rs7566605) upstream of the insulin-induced gene 2 (
INSIG2
) was shown to influence body mass index and obesity in the Framingham Heart Study, with replication of these results in an additional 4 of 5 studies. However, other studies could not replicate the association. Because
INSIG2
plays an important role in cholesterol biosynthesis, we hypothesized that human
INSIG2
variants might play a role in the regulation of plasma lipid and lipoprotein levels.
Methods and Results—
We selected tagging SNPs spanning >100 kb of
INSIG2
locus and sequenced 18 434 base pairs to discover novel SNPs. Thirty-two SNPs were genotyped in 645 individuals from the Quebec Family Study. Two SNPs (rs10490626 and rs12464355) were associated with plasma low-density lipoprotein cholesterol (LDL-C) (
P
<0.0015) and total apolipoprotein B (apoB) levels (
P
<0.014), whereas no association was found between any SNP and body mass index. We replicated the finding of rs10490626 for both LDL-C and total apoB in additional study samples, including 758 individuals from Saguenay–Lac St. Jean, Quebec (
P
=0.040 for LDL-C,
P
=0.044 for apoB), 3247 Europeans (
P
=0.028 for LDL-C,
P
=0.030 for apoB), and 1695 South Asians (
P
=0.0036 for LDL-C,
P
=0.034 for apoB) from the INTERHEART study (for LDL-C, the combined 2-sided
P
=6.2×10
−5
and for total apoB,
P
=0.0011). Furthermore, we identified a variant in the human sorbin and SH
3
-domain–containing-1 gene that was associated with
INSIG2
mRNA levels, and this SNP was shown to act in combination with rs10490626 to affect LDL-C (
P
=0.022) in the Quebec Family Study and in INTERHEART South Asians (
P
=0.019) and Europeans (
P
=0.052).
Conclusion—
These results suggest that
INSIG2
genetic variants may have a more direct role in lipid and lipoprotein metabolism than in obesity.
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Affiliation(s)
- Ron Do
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Swneke D. Bailey
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Guillaume Paré
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Alexandre Montpetit
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Katia Desbiens
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Thomas J. Hudson
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Salim Yusuf
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Claude Bouchard
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Daniel Gaudet
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Louis Pérusse
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Sonia Anand
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Marie-Claude Vohl
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - Tomi Pastinen
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
| | - James C. Engert
- From the Department of Human Genetics (R.D., S.D.B, G.P., T.P., J.C.E.), McGill University, McGill University and Genome Québec Innovation Centre (G.P., A.M., T.J.H., T.P.); and Research Institute of McGill University Health Centre (K.D., J.C.E.), Montreal, Canada; Pennington Biomedical Research Center (C.B.), Baton Rouge, La; Department of Medicine (D.G.), University of Montreal, and ECOGENE-21 Clinical Research Center, Chicoutimi Hospital; Department of Social and Preventive Medicine (L.P.),
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Fornage M, Papanicolaou G, Lewis CE, Boerwinkle E, Siscovick DS. Common INSIG2 polymorphisms are associated with age-related changes in body size and high-density lipoprotein cholesterol from young adulthood to middle age. Metabolism 2010; 59:1084-91. [PMID: 20045156 PMCID: PMC2888786 DOI: 10.1016/j.metabol.2009.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Revised: 10/09/2009] [Accepted: 11/02/2009] [Indexed: 02/07/2023]
Abstract
Insulin-induced gene 2 (INSIG2) plays an important role in the regulation of cholesterol and fatty acids synthesis. A polymorphism, rs7566605, located 10 kilobases upstream of the INSIG2 gene, was identified in a genomewide association study of obesity. We conducted an association study of 12 INSIG2 tag-single nucleotide polymorphisms with longitudinal measures of body size (body mass index and waist circumference) and lipid metabolism (plasma high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides levels). We investigated their interaction with age in 4304 Coronary Artery Risk Development in Young Adults participants (49.5% blacks, 50.5% whites) followed prospectively for 20 years. rs7566605 was not associated with variation in body size or lipid metabolism at any age in either racial group. However, rs1352083 and rs10185316 were associated with age-related decline in high-density lipoprotein cholesterol in whites (P = .0005 and .04, respectively). A similar trend was observed in blacks who consistently maintained a body mass index less than 25 kg/m(2) over the study period. These data support a role of INSIG2 sequence variation in the regulation of cholesterol metabolism.
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Affiliation(s)
- Myriam Fornage
- Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, TX, USA.
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15
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Murphy A, T Weiss S, Lange C. Two-stage testing strategies for genome-wide association studies in family-based designs. Methods Mol Biol 2010; 620:485-496. [PMID: 20652517 DOI: 10.1007/978-1-60761-580-4_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The analysis of genome-wide association studies (GWAS) poses statistical hurdles that have to be handled efficiently in order for the study to be successful. The two largest impediments in the analysis phase of the study are the multiple comparisons problem and maintaining robustness against confounding due to population admixture and stratification. For quantitative traits in family-based designs, Van Steen (1) proposed a two-stage testing strategy that can be considered a hybrid approach between family-based and population-based analysis. By including the population-based component into the family-based analysis, the Van Steen algorithm maximizes the statistical power, while at the same time, maintains the original robustness of family-based association tests (FBATs) (2-4). The Van Steen approach consists of two statistically independent steps, a screening step and a testing step. For all genotyped single nucleotide polymorphisms (SNPs), the screening step examines the evidence for association at a population-based level. Based on support for a potential genetic association from the screening step, the SNPs are prioritized for testing in the next step, where they are analyzed with a FBAT (3). By exploiting population-based information in the screening step that is not utilized in family-based association testing step, the two steps are statistically independent. Therefore, the use of the population-based data for the purposes of screening does not bias the FBAT statistic calculated in the testing step. Depending on the trait type and the ascertainment conditions, Van Steen-type testing strategies can achieve statistical power levels that are comparable to those of population-based studies with the same number of probands. In this chapter, we review the original Van Steen algorithm, its numerous extensions, and discuss its advantages and disadvantages.
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Affiliation(s)
- Amy Murphy
- Channing Laboratory, Center for Genomic Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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16
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Deka R, Xu L, Pal P, Toelupe PT, Laumoli TS, Xi H, Zhang G, Weeks DE, McGarvey ST. A tagging SNP in INSIG2 is associated with obesity-related phenotypes among Samoans. BMC MEDICAL GENETICS 2009; 10:143. [PMID: 20028541 PMCID: PMC2804583 DOI: 10.1186/1471-2350-10-143] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Accepted: 12/22/2009] [Indexed: 11/30/2022]
Abstract
Background A genome wide association study found significant association of a sequence variant, rs7566605, in the insulin-induced gene 2 (INSIG2) with obesity. However, the association remained inconclusive in follow-up studies. We tested for association of four tagging SNPs (tagSNPs) including this variant with body mass index (BMI) and abdominal circumference (ABDCIR) in the Samoans of the Western Pacific, a population with high levels of obesity. Methods We studied 907 adult Samoan participants from a longitudinal study of adiposity and cardiovascular disease risk in two polities, American Samoa and Samoa. Four tagSNPs were identified from the Chinese HapMap database based on pairwise r2 of ≥0.8 and minor allele frequency of ≥0.05. Genotyping was performed using the TaqMan assay. Tests of association with BMI and ABDCIR were performed under the additive model. Results We did not find association of rs7566605 with either BMI or ABDCIR in any group of the Samoans. However, the most distally located tagSNPs in Intron 3 of the gene, rs9308762, showed significant association with both BMI (p-value 0.024) and ABDCIR (p-value 0.009) in the combined sample and with BMI (p-value 0.038) in the sample from Samoa. Conclusion Although rs7566605 was not significantly associated with obesity in our study population, we can not rule out the involvement of INSIG2 in obesity related traits as we found significant association of another tagSNP in INSIG2 with both BMI and ABDCIR. This study suggests the importance of comprehensive assessment of sequence variants within a gene in association studies.
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Affiliation(s)
- Ranjan Deka
- Center for Genome Information, Department of Environmental Health, University of Cincinnati College of Medicine, 3223 Eden Avenue, Cincinnati, OH 45267, USA.
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17
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Gallicchio L, Chang HH, Christo DK, Thuita L, Huang HY, Strickland P, Ruczinski I, Clipp S, Helzlsouer KJ. Single nucleotide polymorphisms in obesity-related genes and all-cause and cause-specific mortality: a prospective cohort study. BMC MEDICAL GENETICS 2009; 10:103. [PMID: 19818126 PMCID: PMC2763854 DOI: 10.1186/1471-2350-10-103] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Accepted: 10/09/2009] [Indexed: 01/06/2023]
Abstract
Background The aim of this study was to examine the associations between 16 specific single nucleotide polymorphisms (SNPs) in 8 obesity-related genes and overall and cause-specific mortality. We also examined the associations between the SNPs and body mass index (BMI) and change in BMI over time. Methods Data were analyzed from 9,919 individuals who participated in two large community-based cohort studies conducted in Washington County, Maryland in 1974 (CLUE I) and 1989 (CLUE II). DNA from blood collected in 1989 was genotyped for 16 SNPs in 8 obesity-related genes: monoamine oxidase A (MAOA), lipoprotein lipase (LPL), paraoxonase 1 and 2 (PON1 and PON2), leptin receptor (LEPR), tumor necrosis factor-α (TNFα), and peroxisome proliferative activated receptor-γ and -δ (PPARG and PPARD). Data on height and weight in 1989 (CLUE II baseline) and at age 21 were collected from participants at the time of blood collection. All participants were followed from 1989 to the date of death or the end of follow-up in 2005. Cox proportional hazards regression was used to obtain the relative risk (RR) estimates and 95% confidence intervals (CI) for each SNP and mortality outcomes. Results The results showed no patterns of association for the selected SNPs and the all-cause and cause-specific mortality outcomes, although statistically significant associations (p < 0.05) were observed between PPARG rs4684847 and all-cause mortality (CC: reference; CT: RR 0.99, 95% CI 0.89, 1.11; TT: RR 0.60, 95% CI 0.39, 0.93) and cancer-related mortality (CC: reference; CT: RR 1.01, 95% CI 0.82, 1.25; TT: RR 0.22, 95% CI 0.06, 0.90) and TNFα rs1799964 and cancer-related mortality (TT: reference; CT: RR 1.23, 95% CI 1.03, 1.47; CC: RR 0.83, 95% CI 0.54, 1.28). Additional analyses showed significant associations between SNPs in LEPR with BMI (rs1137101) and change in BMI over time (rs1045895 and rs1137101). Conclusion Findings from this cohort study suggest that the selected SNPs are not associated with overall or cause-specific death, although several LEPR SNPs may be related to BMI and BMI change over time.
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Affiliation(s)
- Lisa Gallicchio
- The Prevention and Research Center, The Weinberg Center for Women's Health & Medicine, Mercy Medical Center, Baltimore, Maryland 21202, USA.
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18
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Cha S, Koo I, Choi SM, Park BL, Kim KS, Kim JR, Shin HD, Kim JY. Association analyses of the INSIG2 polymorphism in the obesity and cholesterol levels of Korean populations. BMC MEDICAL GENETICS 2009; 10:96. [PMID: 19772594 PMCID: PMC2759923 DOI: 10.1186/1471-2350-10-96] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Accepted: 09/22/2009] [Indexed: 12/14/2022]
Abstract
Background While INSIG2 has been reported to be associated with BMI in many populations, conflicting results have prevented consensus over its role. In analyses of mice and cell cultures the gene has been found to be involved in the regulation of cholesterol synthesis; however, no relationship has been found with cholesterol metabolism in human epidemiological research. Therefore, this study attempts to assess the effect of rs7566605 near INSIG2 on both obesity- and cholesterol-related traits in Koreans. Methods The rs7566605 polymorphism was genotyped with 2,364 Koreans, and associations with obesity- and cholesterol-related traits were analyzed statistically via an ANOVA or T-test. Results Replication of an association with BMI, WHR, fat mass, fat percent, and abdominal fat area failed, and the C allele of rs7566605 was not associated significantly with total cholesterol, HDL cholesterol, or triglyceride. However, it was found in a meta-analysis of a dominant model that the C allele of rs7566605 appeared to affect the level of the total cholesterol, especially in female subjects. Conclusion We failed to show associations of rs7566605 with cholesterol- and obesity-related phenotypes, although we newly suggest the possible involvement of INSIG2 with the plasma level of the total cholesterol in women.
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Affiliation(s)
- Seongwon Cha
- Division of Constitutional Medicine Research, Korea Institute of Oriental Medicine, 483 Exporo, Daejeon, Republic of Korea.
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de Krom M, Bauer F, Collier D, Adan RAH, la Fleur SE. Genetic variation and effects on human eating behavior. Annu Rev Nutr 2009; 29:283-304. [PMID: 19400703 DOI: 10.1146/annurev-nutr-080508-141124] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Feeding is a physiological process, influenced by genetic factors and the environment. In recent years, many studies have been performed to unravel the involvement of genetics in both eating behavior and its pathological forms: eating disorders and obesity. In this review, we provide a condensed introduction on the neurological aspects of eating and we describe the current status of research into the genetics of eating behavior, primarily focused on specific traits such as taste, satiation, and hunger. This is followed by an overview on the genetic studies done to unravel the heritable background of obesity and eating disorders. We examine the discussion currently taking place in the field of genetics of complex disorders and phenotypes on how to perform good and powerful studies, with the use of large-scale whole-genome association studies as one of the possible solutions. In the final part of this review, we give our view on the latest developments, including endophenotype approaches and animal studies. Studies of endophenotypes of eating behavior may help to identify core traits that are genetically influenced. Such studies would yield important knowledge on the underlying biological scaffold on which diagnostic criteria for eating disorders could be based and would provide information to influence eating behavior toward healthier living.
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Affiliation(s)
- Mariken de Krom
- Rudolf Magnus Institute of Neuroscience, Department of Neuroscience & Pharmacology, UMC Utrecht, Utrecht, The Netherlands.
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Talbert ME, Langefeld CD, Ziegler JT, Haffner SM, Norris JM, Bowden DW. INSIG2 SNPs associated with obesity and glucose homeostasis traits in Hispanics: the IRAS Family Study. Obesity (Silver Spring) 2009; 17:1554-62. [PMID: 19360016 PMCID: PMC2916685 DOI: 10.1038/oby.2009.94] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The genome-wide association study by Herbert et al. identified the INSIG2 single-nucleotide polymorphism (SNP) rs7566605 as contributing to increased BMI in ethnically distinct cohorts. The present study sought to further clarify the matter, by testing whether SNPs of INSIG2 influenced quantitative adiposity or glucose homeostasis traits in Hispanics of the Insulin Resistance Atherosclerosis Family Study (IRASFS). Using a tagging SNP approach, rs7566605 and 31 additional SNPs were genotyped in 1,425 IRASFS Hispanics. SNPs were tested for association with six adiposity measures: BMI, waist circumference (WAIST), waist-to-hip ratio (WHR), subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and VAT to SAT ratio (VSR). SNPs were also tested for association with fasting glucose (GFAST), fasting insulin (FINS), and three measures obtained from the frequently sampled intravenous glucose tolerance test: insulin sensitivity (S(I)), acute insulin response (AIR), and disposition index (DI). Most prominent association was observed with direct computed tomography (CT)-measured adiposity phenotypes, including VAT, SAT, and VSR (P values range from 0.007 to 0.044 for rs17586756, rs17047718, rs17047731, rs9308762, rs12623648, and rs11673900). Multiple SNP associations were observed with all glucose homeostasis traits (P values range from 0.001 to 0.031 for rs17047718, rs17047731, rs2161829, rs10490625, rs889904, and rs12623648). Using BMI as a covariate in evaluation of glucose homeostasis traits slightly reduced their association. However, association with adiposity and glucose homeostasis phenotypes is not significant following multiple comparisons adjustment. Trending association after multiple comparisons adjustment remains suggestive of a role for genetic variation of INSIG2 in obesity, but these results require validation.
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Affiliation(s)
- Matthew E Talbert
- Program in Molecular Medicine and Translational Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
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Peeters A, Beckers S, Verrijken A, Mertens I, Van Gaal L, Van Hul W. Possible role for ENPP1 polymorphism in obesity but not for INSIG2 and PLIN variants. Endocrine 2009; 36:103-9. [PMID: 19399648 DOI: 10.1007/s12020-009-9194-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 03/13/2009] [Accepted: 04/01/2009] [Indexed: 10/20/2022]
Abstract
Previous studies have suggested that ENPP1, INSIG2, and PLIN may be linked with a higher risk for obesity or with increased phenotypic measures of obesity. We selected polymorphisms in these candidate genes based on their prior associations with obesity risk or obesity parameters. K121Q (rs1044498) in ENPP1, rs7566605 in INSIG2, and rs894160 in PLIN were genotyped by Taqman assays in a Belgian sample of 1,078 obese subjects (body mass index (BMI) > 30 kg/m(2)) and 323 lean controls (18.5 < BMI < 25 kg/m(2)). BMI, waist circumference, and waist-to-hip ratio (WHR) were assessed by standard methods while a computerized tomography-scan was used to measure visceral (VFA), subcutaneous (SFA), and total (TFA) abdominal fat areas. Presence of the rare allele was not significantly different between cases and controls for the three variants that were tested, while only WHR was associated with ENPP1 in obese subjects. Our data thus indicate that K121Q, rs7566605, and rs894160 are not major contributing factors for obesity.
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Affiliation(s)
- Armand Peeters
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, Wilrijk, 2610, Antwerp, Belgium.
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Vimaleswaran KS, Franks PW, Brage S, Sardinha LB, Andersen LB, Wareham NJ, Ekelund U, Loos RJF. Absence of association between the INSIG2 gene polymorphism (rs7566605) and obesity in the European Youth Heart Study (EYHS). Obesity (Silver Spring) 2009; 17:1453-7. [PMID: 19197262 DOI: 10.1038/oby.2008.650] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The first genome-wide association study for BMI identified a polymorphism, rs7566605, 10 kb upstream of the insulin-induced gene 2 (INSIG2) transcription start site, as the most significantly associated variant in children and adults. Subsequent studies, however, showed inconsistent association of this polymorphism with obesity traits. This polymorphism has been hypothesized to alter INSIG2 expression leading to inhibition of fatty acid and cholesterol synthesis. Hence, we investigated the association of the INSIG2 rs7566605 polymorphism with obesity- and lipid-related traits in Danish and Estonian children (930 boys and 1,073 girls) from the European Youth Heart Study (EYHS), a school-based, cross-sectional study of pre- and early pubertal children. The association between the polymorphism and obesity traits was tested using additive and recessive models adjusted for age, age-group, gender, maturity and country. Interactions were tested by including the interaction terms in the model. Despite having sufficient power (98%) to detect the previously reported effect size for association with BMI, we did not find significant effects of rs7566605 on BMI (additive, P = 0.68; recessive, P = 0.24). Accordingly, the polymorphism was not associated with overweight (P = 0.87) or obesity (P = 0.34). We also did not find association with waist circumference (WC), sum of four skinfolds, or with total cholesterol, triglycerides, low-density lipoprotein, or high-density lipoprotein. There were no gender-specific (P = 0.55), age-group-specific (P = 0.63) or country-specific (P = 0.56) effects. There was also no evidence of interaction between genotype and physical activity (P = 0.95). Despite an adequately powered study, our findings suggest that rs7566605 is not associated with obesity-related traits and lipids in the EYHS.
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Wiedmann S, Neureuther K, Stark K, Reinhard W, Kallmünzer B, Baessler A, Fischer M, Linsel-Nitschke P, Erdmann J, Schunkert H, Hengstenberg C. Lack of association between a common polymorphism near the INSIG2 gene and BMI, myocardial infarction, and cardiovascular risk factors. Obesity (Silver Spring) 2009; 17:1390-5. [PMID: 19197259 DOI: 10.1038/oby.2008.669] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Epidemiological studies revealed an increasing prevalence of and a steep increase in obesity, a risk factor for cardiovascular disease. Because significant influence of a polymorphism, rs7566605, near the INSIG2 gene on BMI has been shown in the general population and in obesity cohorts, we hypothesized that this polymorphism might also act through an elevated BMI on the development of coronary artery disease (CAD) or myocardial infarction (MI). We pursued two strategies: First, the polymorphism rs7566605 was investigated for association with BMI, CAD/MI, and cardiovascular risk factors in a large German cohort at high risk for CAD and MI (n = 1,460 MI patients) as compared to unrelated healthy controls (n = 1,215); second, we extended our analyses on the families of MI patients and performed family-based association testing (n = 5,390 individuals). The polymorphism rs7566605 was analyzed using TaqMan technology. No deviation from Hardy-Weinberg equilibrium could be observed, and the call rate was 98.2%. No significant associations of rs7566605 with CAD/MI, BMI, and classical cardiovascular risk factors could be detected in the full sample size or in the subgroups. A total of 6,878 individuals were investigated in a population of German MI patients and their family members. Although the number of individuals was large enough, no influence of the rs7566605 INSIG2 polymorphism was detected on BMI and CAD/MI. We therefore conclude that in our sample the SNP rs7566605 near the INSIG2 gene does not influence BMI and is not associated directly with CAD/MI or indirectly through cardiovascular risk factors.
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Affiliation(s)
- Silke Wiedmann
- Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Regensburg, Germany
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Bressler J, Fornage M, Hanis CL, Kao WHL, Lewis CE, McPherson R, Dent R, Mosley TH, Pennacchio LA, Boerwinkle E. The INSIG2 rs7566605 genetic variant does not play a major role in obesity in a sample of 24,722 individuals from four cohorts. BMC MEDICAL GENETICS 2009; 10:56. [PMID: 19523229 PMCID: PMC2706232 DOI: 10.1186/1471-2350-10-56] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Accepted: 06/12/2009] [Indexed: 02/08/2023]
Abstract
Background In a genome-wide association study performed in the Framingham Offspring Cohort, individuals homozygous for the rs7566605 C allele located upstream of insulin-induced gene 2 (INSIG2) were reported to incur an increased risk of obesity. This finding was later replicated in four out of five populations examined. The goal of the study reported here was to assess the role of the INSIG2 single nucleotide polymorphism (SNP) in susceptibility to obesity in the prospective longitudinal Atherosclerosis Risk in Communities (ARIC) study (n = 14,566) and in three other cohorts: the Coronary Artery Risk Development in Young Adults (CARDIA) study (n = 3,888), the Genetic Epidemiology Network of Arteriopathy (GENOA) study (n = 4,766), and extremely obese and lean individuals ascertained at the University of Ottawa (n = 1,502). The combined study sample is comprised of 24,722 white, African-American, and Mexican-American participants. Methods Differences in mean body mass index (BMI) and other anthropometric measures including weight, waist circumference, and waist-to-hip ratio were assessed by a general linear model in individuals categorized by INSIG2 rs7566605 genotype. Multivariable logistic regression was used to predict the risk of obesity (BMI ≥ 30 kg/m2). Results There was no discernable variation in the frequencies of the three INSIG2 SNP genotypes observed between white, Hispanic, and African-American obese individuals and non-obese study subjects. When the relationship between rs7566605 and BMI considered either as a categorical variable or a continuous variable was examined, no significant association with obesity was found for participants in any of the four study populations or in a combined analysis (p = 0.38) under a recessive genetic model. There was also no association between the INSIG2 polymorphism and the obesity-related quantitative traits except for a reduced waist-to-hip ratio in white ARIC study participants homozygous for the C allele, and an increased waist-to-hip ratio in African-Americans in the ARIC cohort with the same genotype (p = 0.04 and p = 0.01, respectively). An association with waist-to-hip ratio was not seen when the combined study sample was analyzed (p = 0.74). Conclusion These results suggest that the INSIG2 rs7566605 variant does not play a major role in determining obesity risk in a racially and ethnically diverse sample of 24,722 individuals from four cohorts.
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Affiliation(s)
- Jan Bressler
- Human Genetics Center, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
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Andreasen CH, Mogensen MS, Borch-Johnsen K, Sandbaek A, Lauritzen T, Almind K, Hansen L, Jørgensen T, Pedersen O, Hansen T. Studies of CTNNBL1 and FDFT1 variants and measures of obesity: analyses of quantitative traits and case-control studies in 18,014 Danes. BMC MEDICAL GENETICS 2009; 10:17. [PMID: 19245693 PMCID: PMC2669074 DOI: 10.1186/1471-2350-10-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Accepted: 02/26/2009] [Indexed: 12/18/2022]
Abstract
Background A genome-wide scan in unrelated US Caucasians identified rs7001819 upstream of farnesyl-diphosphate farnesyltransferase 1 (FDFT1) and multiple variants within catenin (cadherin-associated protein), β-like 1 (CTNNBL1) to associate strongly with body mass index (BMI). The most significantly associating variants within CTNNBL1 including rs6013029 and rs6020846 were additionally confirmed to associate with morbid obesity in a French Caucasian case-control sample. The aim of this study was to investigate the impact of these three variants on obesity, through analyses of obesity-related quantitative traits, and case-control studies in large study samples of Danes. Methods The FDFT1 rs7001819, CTNNBL1 rs6013029 and rs6020846 were genotyped, using TaqMan allelic discrimination, in a combined study sample comprising 18,014 participants ascertained from; the population-based Inter99 cohort (n = 6,514), the ADDITION Denmark screening study cohort (n = 8,662), and a population-based sample (n = 680) and a type 2 diabetic patients group (n = 2,158) from Steno Diabetes Center. Results Both CTNNBL1 variants associated with body weight and height with per allele effect sizes of 1.0 [0.3–0.8] kg and 0.6 [0.2–0.9] cm, respectively, for the rs6020846 G-allele. No association was observed with BMI and waist circumference. In case-control studies neither of the CTNNBL1 variants showed association with overweight, obesity or morbid obesity (rs6013029: Odds Ratio (OR)overweight = 1.02 [0.90–1.16], ORobesity = 1.09 [0.95–1.25], ORmorbidobesity = 1.26 [0.91–1.74]; rs6020846: ORoverweight = 1.05 [0.93–1.18], ORobesity= 1.13 [1.00–1.28], ORmorbidobesity = 1.17 [0.86–1.61]). However, in meta-analyses of the present and the previous study, both the rs6013029 T-allele and the rs6020846 G-allele increased the risk of developing morbid obesity (rs6013029: ORcombined = 1.36 [1.12–1.64], p = 0.002; rs6020846: ORcombined = 1.26 [1.06–1.51], p = 0.01), and obesity (rs6013029: ORcombined = 1.17 [1.04–1.31], p = 0.007; rs6020846: ORcombined = 1.17 [1.05–1.30], p = 0.004). The FDFT1 rs7001819 C-allele showed no association with obesity-related quantitative measures or dichotomous measures of overweight, obesity and morbid obesity. Conclusion CTNNBL1 variants associated with body weight and height, and confer the risk of developing obesity in meta-analyses combining the present and a previous study. FDFT1 rs7001819 showed no association with obesity, neither when analysing quantitative traits nor when performing case-control studies of obesity.
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Vogel CIG, Greene B, Scherag A, Müller TD, Friedel S, Grallert H, Heid IM, Illig T, Wichmann HE, Schäfer H, Hebebrand J, Hinney A. Non-replication of an association of CTNNBL1 polymorphisms and obesity in a population of Central European ancestry. BMC MEDICAL GENETICS 2009; 10:14. [PMID: 19228371 PMCID: PMC2669797 DOI: 10.1186/1471-2350-10-14] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Accepted: 02/19/2009] [Indexed: 11/10/2022]
Abstract
BACKGROUND A recent genome-wide association (GWA) study of U.S. Caucasians suggested that eight single nucleotide polymorphisms (SNPs) in CTNNBL1 are associated with obesity and increased fat mass. We analysed the respective SNPs in data from our previously published GWA for early onset obesity (case-control design), in GWA data from a population-based cohort of adults, and in an independent family-based obesity study. We investigated whether variants in CTNNBL1 (including rs6013029) and in three other genes (SH3PXD2B, SLIT3 and FLJ42133,) were associated with obesity. METHODS The GWA studies were carried out using Affymetrix(R) SNP Chips with approximately 500,000 markers each. In the families, SNP rs6013029 was genotyped using the TaqMan(R) allelic discrimination assay. The German case-control GWA included 487 extremely obese children and adolescents and 442 healthy lean individuals. The adult GWA included 1,644 individuals from a German population-based study (KORA). The 775 independent German families consisted of extremely obese children and adolescents and their parents. RESULTS We found no evidence for an association of the reported variants in CTNNBL1 with early onset obesity or increased BMI. Further, in our family-based study we found no evidence for over-transmission of the rs6013029 risk-allele T to obese children. Additionally, we found no evidence for an association of SH3PXD2B, SLIT3 and FLJ42133 variants in our two GWA samples. CONCLUSION We detected no confirmation of the recent association of variants in CTNNBL1 with obesity in a population of Central European ancestry.
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Affiliation(s)
- Carla I G Vogel
- Department of Child and Adolescent Psychiatry, University of Duisburg-Essen, Essen, Germany.
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Wu AC, Gillman MW, Taveras EM, Litonjua AA. INSIG2 is Associated with Lower Gain in Weight-for-Length Between Birth and Age 6 Months. CLINICAL MEDICINE. PEDIATRICS 2009; 3:33-37. [PMID: 20354568 PMCID: PMC2846639 DOI: 10.4137/cmped.s2279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Researchers have described the association of a common DNA polymorphism, rs7566605, near INSIG2 (insulin-induced gene 2) with obesity in multiple independent populations that include subjects ages 11-60 years.1 To our knowledge, no studies have examined the association of this polymorphism with weight status during early childhood. We explored the association of the rs7566605 polymorphism with weight-for-length among 319 children at 6 months and 3 years participating in Project Viva, a pre-birth cohort study. In contrast to studies of older individuals, CC homozygosity was associated with lower gain in weight-for-length z-score between birth and age 6 months than GG homozygosity or GC heterozygosity. At age 3, we did not find an association. The association of INSIG2 gene with obesity may change direction with age.
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Affiliation(s)
- Ann Chen Wu
- Center for Child Health Care Studies, Department of Ambulatory Care and Prevention, Harvard Pilgrim Health Care and Harvard Medical School, Boston, Massachusetts, U.S.A
- Division of General Pediatrics, Children’s Hospital, Boston, Massachusetts, U.S.A
| | - Matthew W. Gillman
- Center for Child Health Care Studies, Department of Ambulatory Care and Prevention, Harvard Pilgrim Health Care and Harvard Medical School, Boston, Massachusetts, U.S.A
- Department of Nutrition, Harvard School of Public Health, Massachusetts, U.S.A
| | - Elsie M. Taveras
- Center for Child Health Care Studies, Department of Ambulatory Care and Prevention, Harvard Pilgrim Health Care and Harvard Medical School, Boston, Massachusetts, U.S.A
- Division of General Pediatrics, Children’s Hospital, Boston, Massachusetts, U.S.A
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Orkunoglu-Suer FE, Gordish-Dressman H, Clarkson PM, Thompson PD, Angelopoulos TJ, Gordon PM, Moyna NM, Pescatello LS, Visich PS, Zoeller RF, Harmon B, Seip RL, Hoffman EP, Devaney JM. INSIG2 gene polymorphism is associated with increased subcutaneous fat in women and poor response to resistance training in men. BMC MEDICAL GENETICS 2008; 9:117. [PMID: 19105843 PMCID: PMC2646703 DOI: 10.1186/1471-2350-9-117] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Accepted: 12/23/2008] [Indexed: 01/27/2023]
Abstract
Background A common SNP upstream of the INSIG2 gene, rs7566605 (g.-10,1025G>C, Chr2:118,552,255, NT_022135.15), was reported to be associated with obesity (Body Mass Index, [BMI]) in a genome-wide association scan using the Framingham Heart Study but has not been reproduced in other cohorts. As BMI is a relatively insensitive measure of adiposity that is subject to many confounding variables, we sought to determine the relationship between the INSIG2 SNP and subcutaneous fat volumes measured by MRI in a young adult population. Methods We genotyped the INSIG2 SNP rs7566605 in college-aged population enrolled in a controlled resistance-training program, (the Functional Polymorphism Associated with Human Muscle Size and Strength, FAMuSS cohort, n = 752 volunteers 18–40 yrs). In this longitudinal study, we examined the effect of the INSIG2 polymorphism on subcutaneous fat and muscle volumes of the upper arm measured by magnetic resonance imaging (MRI) before and after 12 wks of resistance training. Gene/phenotype associations were tested using an analysis of covariance model with age and weight as covariates. Further, the % variation in each phenotype attributable to genotype was determined using hierarchical models and tested with a likelihood ratio test. Results Women with a copy of the C allele had higher levels of baseline subcutaneous fat (GG: n = 139; 243473 ± 5713 mm3 vs. GC/CC: n = 181; 268521 ± 5003 mm3; p = 0.0011); but men did not show any such association. Men homozygous for the G ancestral allele showed a loss of subcutaneous fat, while those with one or two copies of the C allele gained a greater percentage of subcutaneous fat with resistance training (GG: n = 103; 1.02% ± 1.74% vs. GC/CC: n = 93; 6.39% ± 1.82%; p = 0.035). Conclusion Our results show that the INSIG2 rs7566605 polymorphism underlies variation in subcutaneous adiposity in young adult women and suppresses the positive effects of resistance training on men. This supports and extends the original finding that there is an association between measures of obesity and INSIG2 rs7566605 and further implicates this polymorphism in fat regulation.
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Affiliation(s)
- Funda E Orkunoglu-Suer
- Research Center for Genetic Medicine, Children's National Medical Center, Washington, DC 20010, USA.
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Wang HJ, Zhang H, Zhang SW, Pan YP, Ma J. Association of the common genetic variant upstream of INSIG2 gene with obesity related phenotypes in Chinese children and adolescents. BIOMEDICAL AND ENVIRONMENTAL SCIENCES : BES 2008; 21:528-536. [PMID: 19263810 DOI: 10.1016/s0895-3988(09)60013-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE To study the association between the rs7566605 variant of INSIG2 and obesity-related phenotypes in Chinese children and adolescents. METHODS The study sample consisted of two independent cohorts of Chinese children and adolescents. Anthropometric indices, lipids, blood pressure, fasting glucose, insulin and percentage of fat mass were determined. PCR with restriction fragment length polymorphism analysis was performed for genotyping the rs7566605 variant. RESULTS In each of the two independent cohorts, no significant association was observed between rs7566605 and obesity under additive, dominant or recessive model. We also did not detect any difference in the genotype frequency between all the obese children and controls. Furthermore, we did not find evidence of an association between body composition indices and metabolic phenotypes in all children. However, the triglyceride level of CC homozygotes was significantly higher than that of GG+GC genotypes in obese children (P=0.022). Additionally, we observed a non-significant trend of severe obesity in a post-hoc test. CONCLUSION INSIG2 rs7566605 variant is not associated Chinese childhood obesity in two independent cohorts. Further study is needed to verify the effect of rs7566605 on triglyceride in obese children.
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Affiliation(s)
- Hai-Jun Wang
- Department of Maternal and Child Health, School of Public Health, Peking University, Beijing 100191, China
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Andreasen CH, Mogensen MS, Borch-Johnsen K, Sandbæk A, Lauritzen T, Sørensen TIA, Hansen L, Almind K, Jørgensen T, Pedersen O, Hansen T. Non-replication of genome-wide based associations between common variants in INSIG2 and PFKP and obesity in studies of 18,014 Danes. PLoS One 2008; 3:e2872. [PMID: 18682847 PMCID: PMC2483934 DOI: 10.1371/journal.pone.0002872] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Accepted: 07/03/2008] [Indexed: 02/01/2023] Open
Abstract
Background The INSIG2 rs7566605 and PFKP rs6602024 polymorphisms have been identified as obesity gene variants in genome-wide association (GWA) studies. However, replication has been contradictory for both variants. The aims of this study were to validate these obesity-associations through case-control studies and analyses of obesity-related quantitative traits. Moreover, since environmental and genetic factors may modulate the impact of a genetic variant, we wanted to perform such interaction analyses. We focused on physical activity as an environmental risk factor, and on the GWA identified obesity variants in FTO (rs9939609) and near MC4R (rs17782313) as genetic risk factors. Materials and Methods The four variants were genotyped in a combined study sample comprising a total of 18,014 subject ascertained from, the population-based Inter99 cohort (n = 6,514), the ADDITION screening cohort (n = 8,662), a population-based study sample (n = 680) and a type 2 diabetic patient group (n = 2,158) from Steno Diabetes Center. Results No association with overweight, obesity or obesity-related measures was shown for either the INSIG2 rs7566605 or the PFKP rs6602024 variants. However, an interaction between the INSIG2 rs7566605 variant and the level of self-reported physical activity (pInt = 0.004) was observed. A BMI difference of 0.53 (SE 0.42) kg/m2 was found when comparing physically passive homozygous C-allele carriers with physically passive G-allele carriers. No interactions between the two variants and FTO rs9939609 and MC4R rs17782313 were observed. Conclusions The INSIG2 rs7566605 and PFKP rs6602024 polymorphisms play no apparent role in the development of common forms of obesity in the Danish population. However, if replicated, the INSIG2 rs7566605 may influence the level of BMI in combination with the level of physical activity.
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Affiliation(s)
- Camilla H. Andreasen
- Steno Diabetes Center, Copenhagen, Denmark
- Medical and Science, Developmental Projects, Novo Nordisk A/S, Bagsværd, Denmark
- * E-mail:
| | | | - Knut Borch-Johnsen
- Steno Diabetes Center, Copenhagen, Denmark
- Research Centre for Prevention and Health, Glostrup University Hospital, Glostrup, Denmark
- Faculty of Health Science, University of Aarhus, Aarhus, Denmark
| | - Annelli Sandbæk
- Department of General Practice, University of Aarhus, Aarhus, Denmark
| | - Torsten Lauritzen
- Department of General Practice, University of Aarhus, Aarhus, Denmark
| | - Thorkild I. A. Sørensen
- Institute for Preventive Medicine, Copenhagen University Hospitals, Centre for Health and Society, Copenhagen, Denmark
| | - Lars Hansen
- Bristol-Myers Squibb Co., Princeton, New Jersey, United States of America
| | - Katrine Almind
- Medical and Science, Developmental Projects, Novo Nordisk A/S, Bagsværd, Denmark
| | - Torben Jørgensen
- Research Centre for Prevention and Health, Glostrup University Hospital, Glostrup, Denmark
| | - Oluf Pedersen
- Steno Diabetes Center, Copenhagen, Denmark
- Faculty of Health Science, University of Aarhus, Aarhus, Denmark
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Doecke JD, Zhao ZZ, Stark MS, Green AC, Hayward NK, Montgomery GW, Webb PM, Whiteman DC. Single nucleotide polymorphisms in obesity-related genes and the risk of esophageal cancers. Cancer Epidemiol Biomarkers Prev 2008; 17:1007-12. [PMID: 18398047 DOI: 10.1158/1055-9965.epi-08-0023] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Rates of adenocarcinoma of the esophagus (EAC) and esophagogastric junction (EGJAC) have been rising rapidly in recent decades, in contrast to the declining rates of esophageal squamous cell carcinomas (ESCC). Obesity is a major risk factor for both EAC and EGJAC, but not ESCC, and there is speculation that obesity promotes adenocarcinoma development through endocrine and related pathways. We therefore compared the prevalence of 12 single nucleotide polymorphisms (SNPs) in nine candidate genes previously implicated in obesity pathways (LEP, LEPR, ADIPOQ, POMC, PPARalpha, PPARgamma, RXRgamma, GHRL, and INSIG2) in a large Australian case-control study comprising DNA samples from 260 EAC cases, 301 EGJAC cases, 213 ESCC cases, and 1,352 population controls. No SNPs were associated with EGJAC or ESCC. Although several SNPs seemed to be associated with EAC on crude analysis [ADIPOQ (rs1501299), LEP (5'-untranslated region), PPARgamma (H447H), and GHRL (M72L)], effect sizes were modest and none of the associations was significant after correcting for multiple comparisons. Further, we found no consistent evidence that any of the genotypes were associated with risk of EAC or EGJAC within strata of body mass index (<25.0 kg/m(2), 25.0-29.9 kg/m(2), >30 kg/m(2)). In conclusion, our data suggest that these SNPs do not play a major role in esophageal carcinogenesis.
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Affiliation(s)
- James D Doecke
- Division of Population Studies and Human Genetics, Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Brisbane, Queensland, Australia
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INSIG2 gene rs7566605 polymorphism is associated with severe obesity in Japanese. J Hum Genet 2008; 53:857-862. [PMID: 18615239 PMCID: PMC2522377 DOI: 10.1007/s10038-008-0317-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Accepted: 06/18/2008] [Indexed: 12/15/2022]
Abstract
The single nucleotide polymorphism (SNP) rs7566605 in the upstream region of the insulin-induced gene 2 (INSIG2) is associated with the obesity phenotype in many Caucasian populations. In Japanese, this association with the obesity phenotype is not clear. To investigate the relationship between rs7566605 and obesity in Japanese, we genotyped rs7566605 from severely obese subjects [n = 908, body mass index (BMI) ≥ 30 kg/m2] and normal-weight control subjects (n = 1495, BMI < 25 kg/m2). A case–control association analysis revealed that rs7566605 was significantly associated with obesity in Japanese. The P value in the minor allele recessive mode was 0.00020, and the odds ratio (OR) adjusted for gender and age was 1.61 [95% confidential interval (CI) = 1.24–2.09]. Obesity-associated phenotypes, which included the level of BMI, plasma glucose, hemoglobin A1c, total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, and blood pressure, were not associated with the rs7566605 genotype. Thus, rs7566605 in the upstream region of the INSIG2 gene was found to be associated with obesity, i.e., severe obesity, in Japanese.
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Edwards KL, Hutter CM, Wan JY, Kim H, Monks SA. Genome-wide linkage scan for the metabolic syndrome: the GENNID study. Obesity (Silver Spring) 2008; 16:1596-601. [PMID: 18421265 DOI: 10.1038/oby.2008.236] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In the United States, the metabolic syndrome (MetS) constitutes a major public health problem with over 47 million persons meeting clinical criteria for MetS. Numerous studies have suggested genetic susceptibility to MetS. The goals of this study were (i) to identify susceptibility loci for MetS in well-characterized families with type 2 diabetes (T2D) in four ethnic groups and (ii) to determine whether evidence for linkage varies across the four groups. The GENNID study (Genetics of NIDDM) is a multicenter study established by the American Diabetes Association in 1993 and comprises a comprehensive, well-characterized resource of T2D families from four ethnic groups (whites, Mexican Americans, African Americans, and Japanese Americans). Principal component factor analysis (PCFA) was used to define quantitative phenotypes of the MetS. Variance components linkage analysis was conducted using microsatellite markers from a 10-cM genome-wide linkage scan, separately in each of the four ethnic groups. Three quantitative MetS factors were identified by PCFA and used as phenotypes for MetS: (i) a weight/waist factor, (ii) a blood pressure factor, and (iii) a lipid factor. Evidence for linkage to each of these factors was observed. For each ethnic group, our results suggest that several regions harbor susceptibility genes for the MetS. The strongest evidence for linkage for MetS phenotypes was observed on chromosome 2 (2q12.1-2q13) in the white sample and on chromosome 3 (3q26.1-3q29) in the Mexican-American sample. In conclusion, the results suggest that several regions harbor MetS susceptibility genes and that heterogeneity may exist across groups.
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Affiliation(s)
- Karen L Edwards
- Department of Epidemiology, School of Public Health and Community Medicine, University of Washington, Seattle, Washington, USA.
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A roadmap to disentangle the molecular etiology of schizophrenia. Eur Psychiatry 2008; 23:224-32. [PMID: 18583106 DOI: 10.1016/j.eurpsy.2008.02.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Revised: 12/08/2007] [Accepted: 02/26/2008] [Indexed: 12/17/2022] Open
Abstract
Schizophrenia is a severe mental disorder striking mainly young adults and leading to life-long disability in a substantial portion of the sufferers. On the other hand, substantial knowledge about its etiology and pathogenesis is still lacking. Therefore the European Science Foundation (ESF) sponsored a meeting of a panel of European experts on schizophrenia research to discuss the state of art and future perspectives of key topics in this area. The fields covered genetics, epidemiology, animal models, molecular neuropathology and imaging. This was a first step to establish a network of European groups dedicated to Schizophrenia research. The coming calls of the frame work program will be used to strengthen this network in order to achieve substantial progress in understanding and treating this devastating illness.
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The single nucleotide polymorphism upstream of insulin-induced gene 2 (INSIG2) is associated with the prevalence of hypercholesterolaemia, but not with obesity, in Japanese American women. Br J Nutr 2008; 101:322-7. [DOI: 10.1017/s0007114508006557] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Insulin-induced gene 2 (insig-2) protein is known to play important roles in cholesterol and TAG metabolism bothin vivoandin vitro. One particularly interesting single nucleotide polymorphism (SNP), rs7566605, located 10 kb upstream ofINSIG2was reported to have the strongest association with obesity among 86 604 SNP, while the relationship with dyslipidaemia is uncertain. Eight hundred and eighty-five Japanese Americans (347 men and 538 women) and 378 Japanese (182 men and 196 women) were enrolled, and the rs7566605 SNP, which is consistent with either G or C, was determined. We investigated the association between the rs7566605 SNP and the prevalence of hypercholesterolaemia or hypertriacylglycerolaemia, or obesity parameters, as assessed by BMI, waist girth and percentage body fat. There were no significant differences in BMI, waist girth and percentage body fat according to the genotype in each of the four groups, which was divided by population and sex. The prevalence of hypercholesterolaemia was significantly different between the genotypes in Japanese American female subjects (GG, 62·2 %; GC, 57·1 %; CC, 42·1 %;P = 0·021), but not in the other subjects. In Japanese American women, the subjects with the CC genotype had a 0·43-fold decreased risk (95 % CI 0·24, 0·80) for hypercholesterolaemia compared with the GG genotype after adjustment for age, percentage body fat, smoking status and hormone replacement therapy. The CC genotype of the rs7566605 SNP is suggested to be a protective genetic factor against the progression of hypercholesterolaemia on a high-fat diet, especially in Japanese female subjects.
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Liu YJ, Liu XG, Wang L, Dina C, Yan H, Liu JF, Levy S, Papasian CJ, Drees BM, Hamilton JJ, Meyre D, Delplanque J, Pei YF, Zhang L, Recker RR, Froguel P, Deng HW. Genome-wide association scans identified CTNNBL1 as a novel gene for obesity. Hum Mol Genet 2008; 17:1803-13. [PMID: 18325910 PMCID: PMC2900891 DOI: 10.1093/hmg/ddn072] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2007] [Accepted: 03/04/2008] [Indexed: 12/21/2022] Open
Abstract
Obesity is a major public health problem with strong genetic determination; however, the genetic factors underlying obesity are largely unknown. In this study, we performed a genome-wide association scan for obesity by examining approximately 500 000 single-nucleotide polymorphisms (SNPs) in a sample of 1000 unrelated US Caucasians. We identified a novel gene, CTNNBL1, which has multiple SNPs associated with body mass index (BMI) and fat mass. The most significant SNP, rs6013029, achieved experiment-wise P-values of 2.69 x 10(-7) for BMI and of 4.99 x 10(-8) for fat mass, respectively. The SNP rs6013029 minor allele T confers an average increase in BMI and fat mass of 2.67 kg/m(2) and 5.96 kg, respectively, compared with the alternative allele G. We further genotyped the five most significant CTNNBL1 SNPs in a French case-control sample comprising 896 class III obese adults (BMI > or = 40 kg/m(2)) and 2916 lean adults (BMI < 25 kg/m(2)). All five SNPs showed consistent associations with obesity (8.83 x 10(-3) < P < 6.96 x 10(-4)). Those subjects who were homozygous for the rs6013029 T allele had 1.42-fold increased odds of obesity compared with those without the T allele. The protein structure of CTNNBL1 is homologous to beta-catenin, a family of proteins containing armadillo repeats, suggesting similar biological functions. beta-Catenin is involved in the Wnt/beta-catenin-signaling pathway which appears to contribute to maintaining the undifferentiated state of pre-adipocytes by inhibiting adipogenic gene expression. Our study hence suggests a novel mechanism for the development of obesity, where CTNNBL1 may play an important role. Our study also provided supportive evidence for previously identified associations between obesity and INSIG2 and PFKP, but not FTO.
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Affiliation(s)
- Yong-Jun Liu
- School of Medicine, University of Missouri—Kansas City, Kansas City, MO 64108, USA
| | - Xiao-Gang Liu
- School of Medicine, University of Missouri—Kansas City, Kansas City, MO 64108, USA
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education and Institute of Molecular Genetics, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Liang Wang
- School of Medicine, University of Missouri—Kansas City, Kansas City, MO 64108, USA
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education and Institute of Molecular Genetics, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Christian Dina
- CNRS-8090-Institute of Biology, Pasteur Institute, Lille, France
| | - Han Yan
- School of Medicine, University of Missouri—Kansas City, Kansas City, MO 64108, USA
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education and Institute of Molecular Genetics, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Jian-Feng Liu
- School of Medicine, University of Missouri—Kansas City, Kansas City, MO 64108, USA
| | - Shawn Levy
- Vanderbilt Microarray Shared Resource, Vanderbilt University, Nashville, TN 37232, USA
| | | | - Betty M. Drees
- School of Medicine, University of Missouri—Kansas City, Kansas City, MO 64108, USA
| | - James J. Hamilton
- School of Medicine, University of Missouri—Kansas City, Kansas City, MO 64108, USA
| | - David Meyre
- CNRS-8090-Institute of Biology, Pasteur Institute, Lille, France
| | | | - Yu-Fang Pei
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education and Institute of Molecular Genetics, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Lei Zhang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education and Institute of Molecular Genetics, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
| | - Robert R. Recker
- Osteoporosis Research Center, Creighton University, Omaha, NE 68131, USA
| | - Philippe Froguel
- CNRS-8090-Institute of Biology, Pasteur Institute, Lille, France
- Genomic Medicine, Hammersmith Hospital, Imperial College London, London, UK
| | - Hong-Wen Deng
- School of Medicine, University of Missouri—Kansas City, Kansas City, MO 64108, USA
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education and Institute of Molecular Genetics, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, P. R. China
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Hunan Normal University, Changsha, Hunan 410081, P. R. China
- Osteoporosis Research Center, Creighton University, Omaha, NE 68131, USA
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Krapivner S, Popov S, Chernogubova E, Hellénius ML, Fisher RM, Hamsten A, van't Hooft FM. Insulin-induced gene 2 involvement in human adipocyte metabolism and body weight regulation. J Clin Endocrinol Metab 2008; 93:1995-2001. [PMID: 18319320 DOI: 10.1210/jc.2007-1850] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
BACKGROUND Insulin-induced genes (INSIGs) encode proteins that block proteolytic activation of sterol regulatory element-binding proteins, transcription factors that regulate lipogenic enzymes, and adipocyte differentiation. OBJECTIVE Here, we analyzed the relative significance of INSIG1 and INSIG2 in human liver and adipocyte metabolism, and defined a novel, functional polymorphism in the promoter of INSIG2 associated with body mass index. RESEARCH METHODS Variations in gene expression of different human tissues, of hepatoma cells exposed to INSIG1 and INSIG2 gene silencing probes, and of differentiating 3T3-L1 adipocytes were determined by real-time quantitative PCR. The functional significance of a novel polymorphism in the promoter of INSIG2 was analyzed using in vitro methods and gene expression analysis of human adipose tissue, whereas the phenotype associated with this polymorphism was studied in two cohorts of middle-aged men. RESULTS Gene expression analysis of 17 human tissues demonstrated that INSIG1 is highly expressed in the liver, whereas INSIG2 is ubiquitously expressed. Gene silencing experiments confirmed that INSIG1, but not INSIG2, regulates the expression of sterol regulatory element-binding proteins target genes in human hepatoma cells. In contrast, adipocyte differentiation of 3T3-L1 cells was associated with a 13-fold increase in expression of INSIG2. Significant relationships between the INSIG2-102G/A polymorphism and body mass index were observed in two cohorts of middle-aged men (ANOVA P = 0.017 and 0.044, respectively). In vitro studies and analysis of allele-specific expression in human adipose tissue substantiated the functional significance of the INSIG2-102G/A polymorphism. CONCLUSION INSIG2 is involved in adipocyte metabolism and body weight regulation.
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Affiliation(s)
- Sergey Krapivner
- Atherosclerosis Research Unit, Department of Medicine Solna, Karolinska University Hospital, Stockholm, Sweden
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Boes E, Kollerits B, Heid IM, Hunt SC, Pichler M, Paulweber B, Coassin S, Adams TD, Hopkins PN, Lingenhel A, Wagner SA, Kronenberg F. INSIG2 polymorphism is neither associated with BMI nor with phenotypes of lipoprotein metabolism. Obesity (Silver Spring) 2008; 16:827-33. [PMID: 18239574 DOI: 10.1038/oby.2007.132] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE A previous epidemiological study showed an association of the insulin-induced gene 2 (INSIG2) gene with BMI. Additionally, experimental investigations in animals and cell culture provided evidence that this gene might be involved in lipoprotein and free fatty acid (FFA) metabolism. Therefore, the aim of this study was to examine the association between the rs7566605 variant near the INSIG2 gene and BMI and to extend it to other quantitative measures of obesity, as well as parameters of lipoprotein and FFA metabolism. METHODS AND PROCEDURES We genotyped rs7566605 in a group of severely obese white patients (n = 1,026) with an average BMI of 46.0 kg/m(2) and a control group (n = 818) from Utah, as well as in the Salzburg Atherosclerosis Prevention Program in Subjects at High Individual Risk (SAPHIR) study from Austria, which is based on a healthy working population (n = 1,696). RESULTS We observed no difference in the genotype frequency of rs7566605 of INSIG2 between obese subjects and population-based controls from Utah. Furthermore, we did not find evidence of an association with measures of body composition (BMI, waist, waist-to-hip ratio, percentage body fat, amount of visceral and subcutaneous abdominal adipose fat) or lipoprotein metabolism (total cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, triglycerides, and FFAs) in the Utah study population or in the independent SAPHIR study. DISCUSSION Our results do not support an association of the INSIG2 gene with the regulation of body weight or parameters related to lipoprotein metabolism.
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Affiliation(s)
- Eva Boes
- Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, Innsbruck, Austria
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Abstract
PURPOSE OF REVIEW Over the past two decades serious efforts has been invested in the search for genes that predispose to common obesity, but progress has been slow and success limited. Genome-wide association, however, has revived optimism. Here we review recent advances in the field of obesity genetics and discuss the most important findings of candidate gene, genome-wide linkage studies and genome-wide association studies. We conclude by speculating about the way forward in the near future. RECENT FINDINGS Although large-scale candidate gene studies have placed MC4R more firmly on the human obesity map, the major breakthrough in obesity genetics was the discovery of FTO through genome-wide association. Variants located in the first intron of FTO were unequivocally associated with a 1.67-fold increased risk for obesity and a 0.40-0.66 kg/m2 increase in body mass index. SUMMARY Genome-wide association promises to enhance greatly our understanding of the genetic basis of common obesity, although candidate gene studies will remain a valuable approach because they allow more detailed analyses of biologically relevant candidates. A key factor contributing to continued success lies in large-scale data integration through international collaboration, which will provide the sample sizes required to identify genetic association with conclusive evidence.
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Affiliation(s)
- Shengxu Li
- Medical Research Council Epidemiology Unit, Institute of Metabolic Science, Cambridge, UK
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Lasky-Su J, Lyon HN, Emilsson V, Heid IM, Molony C, Raby BA, Lazarus R, Klanderman B, Soto-Quiros ME, Avila L, Silverman EK, Thorleifsson G, Thorsteinsdottir U, Kronenberg F, Vollmert C, Illig T, Fox CS, Levy D, Laird N, Ding X, McQueen MB, Butler J, Ardlie K, Papoutsakis C, Dedoussis G, O'Donnell CJ, Wichmann HE, Celedón JC, Schadt E, Hirschhorn J, Weiss ST, Stefansson K, Lange C. On the replication of genetic associations: timing can be everything! Am J Hum Genet 2008; 82:849-58. [PMID: 18387595 PMCID: PMC2427263 DOI: 10.1016/j.ajhg.2008.01.018] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2007] [Revised: 12/10/2007] [Accepted: 01/11/2008] [Indexed: 01/22/2023] Open
Abstract
The failure of researchers to replicate genetic-association findings is most commonly attributed to insufficient statistical power, population stratification, or various forms of between-study heterogeneity or environmental influences.(1) Here, we illustrate another potential cause for nonreplications that has so far not received much attention in the literature. We illustrate that the strength of a genetic effect can vary by age, causing "age-varying associations." If not taken into account during the design and the analysis of a study, age-varying genetic associations can cause nonreplication. By using the 100K SNP scan of the Framingham Heart Study, we identified an age-varying association between a SNP in ROBO1 and obesity and hypothesized an age-gene interaction. This finding was followed up in eight independent samples comprising 13,584 individuals. The association was replicated in five of the eight studies, showing an age-dependent relationship (one-sided combined p = 3.92 x 10(-9), combined p value from pediatric cohorts = 2.21 x 10(-8), combined p value from adult cohorts = 0.00422). Furthermore, this study illustrates that it is difficult for cross-sectional study designs to detect age-varying associations. If the specifics of age- or time-varying genetic effects are not considered in the selection of both the follow-up samples and in the statistical analysis, important genetic associations may be missed.
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Affiliation(s)
- Jessica Lasky-Su
- SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Helen N. Lyon
- Divisions of Genetics and Endocrinology, Program in Genomics, Children's Hospital, Boston, MA 02115, USA
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Valur Emilsson
- deCode Genetics, IS-101 Reykjavik, Iceland
- Rosetta Inpharmatics, Seattle, WA 98109, USA
| | - Iris M. Heid
- GSF National Research Centre for Environment and Health, Institute of Epidemiology, 85764 Neuherberg, Germany
- Institute of Medical Informatics, Biometry, and Epidemiology, Ludwig-Maximilians-University, 80539 Munich, Germany
| | | | - Benjamin A. Raby
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Ross Lazarus
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Barbara Klanderman
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Manuel E. Soto-Quiros
- Division of Pediatric Pulmonology, Hospital Nacional de Niños, PO Box 1654-1000, San José, Costa Rica
| | - Lydiana Avila
- Division of Pediatric Pulmonology, Hospital Nacional de Niños, PO Box 1654-1000, San José, Costa Rica
| | - Edwin K. Silverman
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | | | - Florian Kronenberg
- Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, 6020 Innsbruck, Austria
| | - Caren Vollmert
- GSF National Research Centre for Environment and Health, Institute of Epidemiology, 85764 Neuherberg, Germany
| | - Thomas Illig
- GSF National Research Centre for Environment and Health, Institute of Epidemiology, 85764 Neuherberg, Germany
| | - Caroline S. Fox
- National Heart, Lung, and Blood Institute and its Framingham Heart Study, Framingham, MA 01702, USA
| | - Daniel Levy
- National Heart, Lung, and Blood Institute and its Framingham Heart Study, Framingham, MA 01702, USA
| | - Nan Laird
- Harvard School of Public Health, Boston, MA 02115, USA
| | - Xiao Ding
- Harvard School of Public Health, Boston, MA 02115, USA
| | - Matt B. McQueen
- Institute for Behavioral Genetics, University of Colorado, Boulder, CO 80309, USA
| | - Johannah Butler
- Divisions of Genetics and Endocrinology, Program in Genomics, Children's Hospital, Boston, MA 02115, USA
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Kristin Ardlie
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | | | - George Dedoussis
- Department of Nutrition and Dietetics, Harokopio University, Athens 17671, Greece
| | - Christopher J. O'Donnell
- National Heart, Lung, and Blood Institute and its Framingham Heart Study, Framingham, MA 01702, USA
| | - H.-Erich Wichmann
- GSF National Research Centre for Environment and Health, Institute of Epidemiology, 85764 Neuherberg, Germany
- Institute of Medical Informatics, Biometry, and Epidemiology, Ludwig-Maximilians-University, 80539 Munich, Germany
| | - Juan C. Celedón
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Eric Schadt
- Rosetta Inpharmatics, Seattle, WA 98109, USA
| | - Joel Hirschhorn
- Divisions of Genetics and Endocrinology, Program in Genomics, Children's Hospital, Boston, MA 02115, USA
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Scott T. Weiss
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | - Christoph Lange
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard School of Public Health, Boston, MA 02115, USA
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Reinehr T, Hinney A, Nguyen TT, Hebebrand J. Evidence of an influence of a polymorphism near the INSIG2 on weight loss during a lifestyle intervention in obese children and adolescents. Diabetes 2008; 57:623-6. [PMID: 18003761 DOI: 10.2337/db07-0408] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Homozygotes for the C-allele of the single nucleotide polymorphism (SNP) rs7566605, located approximately 10 kb upstream of insulin-induced gene 2 (INSIG2), showed a slightly increased risk of becoming obese. The aim of this study was to analyze whether children homozygous for the C-allele lose less weight in an intervention than children with the GG- or GC-genotype. RESEARCH DESIGN AND METHODS We genotyped rs7566605 in 293 obese children (mean age 10.8 years, 45% male, mean BMI 28.1 kg/m(2)) who presented for a 1-year intervention. The reduction of SD score (SDS) BMI was compared based on an intention-to-treat analysis between the children with different genotypes. Blood pressure, triglycerides, insulin and glucose concentrations, and total, HDL, and LDL cholesterol were measured before and after intervention. RESULTS After 1 year, obese children with the CC-genotype had reduced their SDS BMI to a lower extent than obese children with GC- or GG-genotypes (recessive model P = 0.007). There was no evidence for an association of rs7566605 with the cardiovascular risk factor profile (nominal P > 0.1). CONCLUSIONS CC-homozygotes at SNP rs7566605 in the vicinity of INSIG2 lost less weight in this lifestyle intervention. This finding further implicates this polymorphism in weight regulation.
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Affiliation(s)
- Thomas Reinehr
- Vestische Hospital for Children and Adolescents, University of Witten/Herdecke, Dr. F. Steiner Str. 5, 45711 Datteln, Germany.
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Yang L, Wu Y, Li H, Yu Z, Li X, Liu Y, Lin X, Chen Y. Potential association of INSIG2 rs7566605 polymorphism with body weight in a Chinese subpopulation. Eur J Hum Genet 2008; 16:759-61. [PMID: 18270535 DOI: 10.1038/ejhg.2008.8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Herbert et al reported association with obesity of a common DNA variant rs7566605 at 10 kb upstream of the INSIG2 gene. We analyzed rs7566605 polymorphism in 3125 Chinese in a cross-sectional study. We found no significant association of rs7566605 polymorphism with body mass index (BMI) and waist circumference among all participants (P=0.52). However, if geographic location is considered, the C/C genotype of rs7566605 was marginally associated with increased levels of BMI and risk of obesity among individuals living in Shanghai (P=0.06), indicating that the C/C genotype may contribute to obesity in certain subpopulation among Chinese under certain environmental settings.
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Affiliation(s)
- Ling Yang
- Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, 294 Taiyuan Road, Shanghai, China
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Gaukrodger N, Avery PJ, Keavney B. Plasma potassium level is associated with common genetic variation in the beta-subunit of the epithelial sodium channel. Am J Physiol Regul Integr Comp Physiol 2008; 294:R1068-72. [PMID: 18184758 DOI: 10.1152/ajpregu.00732.2007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Plasma potassium is a moderately heritable phenotype, but no robust associations between common single nucleotide polymorphisms (SNPs) and plasma potassium have previously been described. Genetic influences on renal potassium handling could be important in the etiology of hypertension. We have tested whether common genetic variation in the gene encoding the beta-subunit of the epithelial sodium channel (SCNN1B) affects plasma potassium and blood pressure level in a study of 1,425 members of 248 families ascertained on a proband with hypertension. We characterized family members for blood pressure using ambulatory monitoring, measured plasma potassium in venous blood samples, and genotyped four SNPs that spanned the SCNN1B gene. We found highly significant association between genotype at the SCNN1B rs889299 SNP situated in intron 4 of the gene and plasma potassium. Homozygotes for the rarer T allele had on average a 0.15 mM lower plasma potassium than homozygotes for the common C allele, with an intermediate value for heterozygotes (trend, P = 0.0003). Genotype at rs889299 accounted for approximately 1% of the total variability in plasma potassium, or around 3% of the total heritable fraction. There was no association between genotype at any SCNN1B SNP and blood pressure considered as a quantitative trait, or with hypertension affection status. We have shown a modest sized but highly significant effect of common genetic variation in the SCNN1B gene on plasma potassium. Interaction between the rs889299 SNP and functional SNPs in other genes influencing aldosterone-responsive distal tubular electrolyte transport may be important in the etiology of essential hypertension.
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Andreasen CH, Stender-Petersen KL, Mogensen MS, Torekov SS, Wegner L, Andersen G, Nielsen AL, Albrechtsen A, Borch-Johnsen K, Rasmussen SS, Clausen JO, Sandbaek A, Lauritzen T, Hansen L, Jørgensen T, Pedersen O, Hansen T. Low physical activity accentuates the effect of the FTO rs9939609 polymorphism on body fat accumulation. Diabetes 2008; 57:95-101. [PMID: 17942823 DOI: 10.2337/db07-0910] [Citation(s) in RCA: 348] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Three independent studies have shown that variation in the fat mass and obesity-associated (FTO) gene associates with BMI and obesity. In the present study, the effect of FTO variation on metabolic traits including obesity, type 2 diabetes, and related quantitative phenotypes was examined. RESEARCH DESIGN AND METHODS The FTO rs9939609 polymorphism was genotyped in a total of 17,508 Danes from five different study groups. RESULTS In studies of 3,856 type 2 diabetic case subjects and 4,861 normal glucose-tolerant control subjects, the minor A-allele of rs9939609 associated with type 2 diabetes (odds ratio 1.13 [95% CI 1.06-1.20], P = 9 x 10(-5)). This association was abolished when adjusting for BMI (1.06 [0.97-1.16], P = 0.2). Among 17,162 middle-aged Danes, the A-allele associated with overweight (1.19 [1.13-1.24], P = 1 x 10(-12)) and obesity (1.27 [1.20-1.34], P = 2 x 10(-16)). Furthermore, obesity-related quantitative traits such as body weight, waist circumference, fat mass, and fasting serum leptin levels were significantly elevated in A-allele carriers. An interaction between the FTO rs9939609 genotype and physical activity (P = 0.007) was found, where physically inactive homozygous risk A-allele carriers had a 1.95 +/- 0.3 kg/m(2) increase in BMI compared with homozygous T-allele carriers. CONCLUSIONS We validate that variation in FTO is associated with type 2 diabetes when not adjusted for BMI and with an overall increase in body fat mass. Furthermore, low physical activity seems to accentuate the effect of FTO rs9939609 on body fat accumulation.
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Affiliation(s)
- Camilla H Andreasen
- Steno Diabetes Center, Niels Steensens Vej 1, NLC2.13, DK-2820 Gentofte, Denmark.
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Pollex RL, Ban MR, Young TK, Bjerregaard P, Anand SS, Yusuf S, Zinman B, Harris SB, Hanley AJG, Connelly PW, Huff MW, Hegele RA. Association between the -455T>C promoter polymorphism of the APOC3 gene and the metabolic syndrome in a multi-ethnic sample. BMC MEDICAL GENETICS 2007; 8:80. [PMID: 18096054 PMCID: PMC2241585 DOI: 10.1186/1471-2350-8-80] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Accepted: 12/20/2007] [Indexed: 12/19/2022]
Abstract
Background Common polymorphisms in the promoter of the APOC3 gene have been associated with hypertriglyceridemia and may impact on phenotypic expression of the metabolic syndrome (MetS). The rs7566605 marker, located near the INSIG2 gene, has been found to be associated with obesity, making it also a potential genetic determinant for MetS. The objective of this study is to examine the APOC3 -455T>C and the INSIG2 rs7566605 polymorphisms as potential genetic determinants for MetS in a multi-ethnic sample. Methods Subjects were genotyped for both the APOC3 -455T>C and INSIG2 rs7566605 polymorphisms, and classified for the presence or absence of MetS (NCEP ATP III and IDF definitions). The total study population included 2675 subjects (≥18 years of age) from six different geographical ancestries. Results For the overall study population, the prevalence of MetS was 22.6% (NCEP ATP III definition). Carriers of ≥1 copy of APOC3 -455C were more likely to have MetS (NCEP ATP III definition) than noncarriers (carrier odds ratio 1.73, 95% CI 1.40 to 2.14, adjusting for age and study group). The basis of the association was related not only to a higher proportion of -455C carriers meeting the triglyceride and high-density lipoprotein cholesterol criteria, but also the blood pressure criteria compared with wild-type homozygotes. Plasma apo C-III concentrations were not associated with APOC3 -455T>C genotype. The INSIG2 rs7566605 polymorphism was not associated with MetS or measures of obesity. Conclusion Meta-analysis of the sample of multiple geographic ancestries indicated that the functional -455T>C promoter polymorphism in APOC3 was associated with an approximately 2-fold increased risk of MetS, whereas the INSIG2 rs7566605 polymorphism was not associated with MetS.
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Affiliation(s)
- Rebecca L Pollex
- Vascular Biology Research Group, Robarts Research Institute, London, Ontario, Canada.
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Chanock SJ, Manolio T, Boehnke M, Boerwinkle E, Hunter DJ, Thomas G, Hirschhorn JN, Abecasis G, Altshuler D, Bailey-Wilson JE, Brooks LD, Cardon LR, Daly M, Donnelly P, Fraumeni JF, Freimer NB, Gerhard DS, Gunter C, Guttmacher AE, Guyer MS, Harris EL, Hoh J, Hoover R, Kong CA, Merikangas KR, Morton CC, Palmer LJ, Phimister EG, Rice JP, Roberts J, Rotimi C, Tucker MA, Vogan KJ, Wacholder S, Wijsman EM, Winn DM, Collins FS. Replicating genotype–phenotype associations. Nature 2007; 447:655-60. [PMID: 17554299 DOI: 10.1038/447655a] [Citation(s) in RCA: 1018] [Impact Index Per Article: 59.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Lyon HN, Emilsson V, Hinney A, Heid IM, Lasky-Su J, Zhu X, Thorleifsson G, Gunnarsdottir S, Walters GB, Thorsteinsdottir U, Kong A, Gulcher J, Nguyen TT, Scherag A, Pfeufer A, Meitinger T, Brönner G, Rief W, Soto-Quiros ME, Avila L, Klanderman B, Raby BA, Silverman EK, Weiss ST, Laird N, Ding X, Groop L, Tuomi T, Isomaa B, Bengtsson K, Butler JL, Cooper RS, Fox CS, O'Donnell CJ, Vollmert C, Celedón JC, Wichmann HE, Hebebrand J, Stefansson K, Lange C, Hirschhorn JN. The association of a SNP upstream of INSIG2 with body mass index is reproduced in several but not all cohorts. PLoS Genet 2007; 3:e61. [PMID: 17465681 PMCID: PMC1857727 DOI: 10.1371/journal.pgen.0030061] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Accepted: 03/06/2007] [Indexed: 12/13/2022] Open
Abstract
A SNP upstream of the INSIG2 gene, rs7566605, was recently found to be associated with obesity as measured by body mass index (BMI) by Herbert and colleagues. The association between increased BMI and homozygosity for the minor allele was first observed in data from a genome-wide association scan of 86,604 SNPs in 923 related individuals from the Framingham Heart Study offspring cohort. The association was reproduced in four additional cohorts, but was not seen in a fifth cohort. To further assess the general reproducibility of this association, we genotyped rs7566605 in nine large cohorts from eight populations across multiple ethnicities (total n = 16,969). We tested this variant for association with BMI in each sample under a recessive model using family-based, population-based, and case-control designs. We observed a significant (p < 0.05) association in five cohorts but saw no association in three other cohorts. There was variability in the strength of association evidence across examination cycles in longitudinal data from unrelated individuals in the Framingham Heart Study Offspring cohort. A combined analysis revealed significant independent validation of this association in both unrelated (p = 0.046) and family-based (p = 0.004) samples. The estimated risk conferred by this allele is small, and could easily be masked by small sample size, population stratification, or other confounders. These validation studies suggest that the original association is less likely to be spurious, but the failure to observe an association in every data set suggests that the effect of SNP rs7566605 on BMI may be heterogeneous across population samples. Obesity is an epidemic in the United States of America and developing world, portending an epidemic of related diseases such as diabetes and heart disease. While diet and lifestyle contribute to obesity, half of the population variation in body mass index, a common measure of obesity, is determined by inherited factors. Many studies have reported that common sequence variants in genes are associated with an increased risk for obesity, yet most of these are not reproducible in other study cohorts, suggesting that some are false. Recently, Herbert et al. reported a slightly increased risk of obesity for people carrying two copies of the minor allele at a common variant near INSIG2. We present our attempts to further evaluate this potential association with obesity in additional populations. We find evidence of increased risk of obesity for people carrying two copies of the minor allele in five out of nine cohorts tested, using both family- and population-based testing. We indicate possible reasons for the varied results, with the hope of encouraging a combined analysis across study cohorts to more precisely define the effect of this INSIG2 gene variant.
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Affiliation(s)
- Helen N Lyon
- Program in Genomics, Divisions of Genetics and Endocrinology, Children's Hospital, Boston, Massachusetts, USA.
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