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Timmers PR, Mounier N, Lall K, Fischer K, Ning Z, Feng X, Bretherick AD, Clark DW, Shen X, Esko T, Kutalik Z, Wilson JF, Joshi PK. Genomics of 1 million parent lifespans implicates novel pathways and common diseases and distinguishes survival chances. eLife 2019; 8:39856. [PMID: 30642433 PMCID: PMC6333444 DOI: 10.7554/elife.39856] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/20/2018] [Indexed: 12/31/2022] Open
Abstract
We use a genome-wide association of 1 million parental lifespans of genotyped subjects and data on mortality risk factors to validate previously unreplicated findings near CDKN2B-AS1, ATXN2/BRAP, FURIN/FES, ZW10, PSORS1C3, and 13q21.31, and identify and replicate novel findings near ABO, ZC3HC1, and IGF2R. We also validate previous findings near 5q33.3/EBF1 and FOXO3, whilst finding contradictory evidence at other loci. Gene set and cell-specific analyses show that expression in foetal brain cells and adult dorsolateral prefrontal cortex is enriched for lifespan variation, as are gene pathways involving lipid proteins and homeostasis, vesicle-mediated transport, and synaptic function. Individual genetic variants that increase dementia, cardiovascular disease, and lung cancer - but not other cancers - explain the most variance. Resulting polygenic scores show a mean lifespan difference of around five years of life across the deciles. Editorial note This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).
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Affiliation(s)
- Paul Rhj Timmers
- Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom
| | - Ninon Mounier
- Institute of Social and Preventive Medicine, University Hospital of Lausanne, Lausanne, Switzerland.,Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Kristi Lall
- Estonian Genome Center, Institute of Genomics, University of Tartu, Tartu, Estonia.,Institute of Mathematics and Statistics, University of Tartu, Tartu, Estonia
| | - Krista Fischer
- Estonian Genome Center, Institute of Genomics, University of Tartu, Tartu, Estonia.,Institute of Mathematics and Statistics, University of Tartu, Tartu, Estonia
| | - Zheng Ning
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Xiao Feng
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Andrew D Bretherick
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - David W Clark
- Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Xia Shen
- Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom.,Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.,State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Tõnu Esko
- Estonian Genome Center, Institute of Genomics, University of Tartu, Tartu, Estonia.,Broad Institute of Harvard and MIT, Cambridge, United States
| | - Zoltán Kutalik
- Institute of Social and Preventive Medicine, University Hospital of Lausanne, Lausanne, Switzerland.,Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - James F Wilson
- Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom.,MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Peter K Joshi
- Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom.,Institute of Social and Preventive Medicine, University Hospital of Lausanne, Lausanne, Switzerland
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Kaabi YA. Frequency of the exon 3-deleted/full-length growth hormone receptor polymorphism in Saudi Arabian population. Saudi Med J 2017; 38:1090-1095. [PMID: 29114695 PMCID: PMC5767610 DOI: 10.15537/smj.2017.11.21109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Objectives: To investigate the frequency of the growth hormone receptor (GHR)-d3 polymorphism in a random sample of Saudi Arabian population from Jazan province, and test the effects of the polymorphism on some anthropometric factors. Methods: This cross-sectional population-based study was conducted during the period from January to April 2017 at the College of Applied Medical Sciences, Jazan University, Southwestern Saudi Arabia. A total of 230 healthy adult male and female volunteers were randomly recruited. Genomic DNA was extracted from the whole blood, and the GHR exon 3 locus was genotyped using multiplex polymerase chain reaction. Results: The distributions of the GHR genotypes were as follows: fl/fl (39.1%), fl/d3 (44.8%), and d3/d3 (16.1%). No statistically significant differences were found between fl/fl, fl/d3, or d3/d3 GHR genotypes in terms of weight (p=0.90), height (p=0.12), or body mass index (BMI) (p=0.83) values. Conclusion: No correlations were found between the GHR-d3 polymorphism and weight, height, or BMI.
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Affiliation(s)
- Yahia A Kaabi
- Department of Medical Laboratory Technology, College of Applied Medical Sciences, Jazan University, Jazan, Kingdom of Saudi Arabia. E-mail.
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Dias C, Giordano M, Frechette R, Bellone S, Polychronakos C, Legault L, Deal CL, Goodyer CG. Genetic variations at the human growth hormone receptor (GHR) gene locus are associated with idiopathic short stature. J Cell Mol Med 2017; 21:2985-2999. [PMID: 28557176 PMCID: PMC5661101 DOI: 10.1111/jcmm.13210] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/17/2017] [Indexed: 12/15/2022] Open
Abstract
GH plays an essential role in the growing child by binding to the growth hormone receptor (GHR) on target cells and regulating multiple growth promoting and metabolic effects. Mutations in the GHR gene coding regions result in GH insensitivity (dwarfism) due to a dysfunctional receptor protein. However, children with idiopathic short stature (ISS) show growth impairment without GH or GHR defects. We hypothesized that decreased expression of the GHR gene may be involved. To test this, we investigated whether common genetic variants (microsatellites, SNPs) in regulatory regions of the GHR gene region were associated with the ISS phenotype. Genotyping of a GT‐repeat microsatellite in the GHR 5′UTR in a Montreal ISS cohort (n = 37 ISS, n = 105 controls) revealed that the incidence of the long/short (L/S) genotype was 3.3× higher in ISS children than controls (P = 0.04, OR = 3.85). In an Italian replication cohort (n = 143 ISS, n = 282 controls), the medium/short (M/S) genotype was 1.9× more frequent in the male ISS than controls (P = 0.017, OR = 2.26). In both ISS cohorts, logistic regression analysis of 27 SNPs showed an association of ISS with rs4292454, while haplotype analysis revealed specific risk haplotypes in the 3′ haploblocks. In contrast, there were no differences in GT genotype frequencies in a cohort of short stature (SS) adults versus controls (CARTaGENE: n = 168 SS, n = 207 controls) and the risk haplotype in the SS cohort was located in the most 5′ haploblock. These data suggest that the variants identified are potentially genetic markers specifically associated with the ISS phenotype.
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Affiliation(s)
- Christel Dias
- Department of Experimental Medicine, McGill University, Montreal, QC, Canada
| | - Mara Giordano
- Laboratory of Human Genetics, Department of Health Science, University of Eastern Piedmont, Novara, Italy
| | | | - Simonetta Bellone
- Division of Pediatrics, Department of Health Science, University of Eastern Piedmont, Novara, Italy
| | - Constantin Polychronakos
- Departments of Experimental Medicine, Human Genetics and Pediatrics, McGill University, Montreal, QC, Canada
| | - Laurent Legault
- Department of Pediatrics, McGill University, Montreal, QC, Canada
| | - Cheri L Deal
- CHU Ste-Justine Research Centre and Department of Pediatrics, Université de Montréal, Montreal, QC, Canada
| | - Cynthia Gates Goodyer
- Department of Experimental Medicine, McGill University, Montreal, QC, Canada.,Departments of Experimental Medicine and Pediatrics, McGill University, Montreal, QC, Canada
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Alfred T, Ben-Shlomo Y, Cooper R, Hardy R, Cooper C, Deary IJ, Gaunt TR, Gunnell D, Harris SE, Kumari M, Martin RM, Sayer AA, Starr JM, Kuh D, Day INM. A multi-cohort study of polymorphisms in the GH/IGF axis and physical capability: the HALCyon programme. PLoS One 2012; 7:e29883. [PMID: 22253814 PMCID: PMC3254646 DOI: 10.1371/journal.pone.0029883] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 12/06/2011] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Low muscle mass and function have been associated with poorer indicators of physical capability in older people, which are in-turn associated with increased mortality rates. The growth hormone/insulin-like growth factor (GH/IGF) axis is involved in muscle function and genetic variants in genes in the axis may influence measures of physical capability. METHODS As part of the Healthy Ageing across the Life Course (HALCyon) programme, men and women from seven UK cohorts aged between 52 and 90 years old were genotyped for six polymorphisms: rs35767 (IGF1), rs7127900 (IGF2), rs2854744 (IGFBP3), rs2943641 (IRS1), rs2665802 (GH1) and the exon-3 deletion of GHR. The polymorphisms have previously been robustly associated with age-related traits or are potentially functional. Meta-analysis was used to pool within-study genotypic effects of the associations between the polymorphisms and four measures of physical capability: grip strength, timed walk or get up and go, chair rises and standing balance. RESULTS Few important associations were observed among the several tests. We found evidence that rs2665802 in GH1 was associated with inability to balance for 5 s (pooled odds ratio per minor allele = 0.90, 95% CI: 0.82-0.98, p-value = 0.01, n = 10,748), after adjusting for age and sex. We found no evidence for other associations between the polymorphisms and physical capability traits. CONCLUSION Our findings do not provide evidence for a substantial influence of these common polymorphisms in the GH/IGF axis on objectively measured physical capability levels in older adults.
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Affiliation(s)
- Tamuno Alfred
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom.
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Shishkin SS, Lisitskaya KV, Krakhmaleva IN. Biochemical polymorphism of the growth hormone system proteins and its manifestations in human prostate cells. BIOCHEMISTRY (MOSCOW) 2011; 75:1547-62. [PMID: 21417994 DOI: 10.1134/s0006297910130043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The basic mechanisms are considered that are responsible for producing biochemical polymorphism of human proteins realized at three basic levels: the structures of genome and genes; the transcription and maturation of transcripts; the postsynthetic formation of functionally active protein products of gene expression. The data on biochemical polymorphism of growth hormone (GH) and some other proteins that are directly or indirectly necessary for its functioning and support this polymorphism by polylocus, polyallelism, alternative splicing, and various postsynthetic modifications are analyzed. The role of polymorphic proteins of the GH system is discussed in formation of a variety of oligomeric molecular structures of this system (multicomponent transport complexes, receptors, and endocellular protein ensembles involved in the regulation of gene expression). It is emphasized that such structural polymorphism significantly influences the biological effects in various parts of the GH system during physiological processes and in tumors, in particular in prostate cancer.
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Affiliation(s)
- S S Shishkin
- Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia.
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McElholm AR, McKnight AJ, Patterson CC, Johnston BT, Hardie LJ, Murray LJ. A population-based study of IGF axis polymorphisms and the esophageal inflammation, metaplasia, adenocarcinoma sequence. Gastroenterology 2010; 139:204-12.e3. [PMID: 20403354 DOI: 10.1053/j.gastro.2010.04.014] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 03/23/2010] [Accepted: 04/08/2010] [Indexed: 12/26/2022]
Abstract
BACKGROUND & AIMS Insulin-like growth factor (IGF) axis plays a key role in cell development, proliferation, and survival and is implicated in the etiology of several cancers. Few studies have examined the relationship between genetic variation of this axis and esophageal adenocarcinoma (EAC) or its precursors. METHODS In a population-based case-control study, we investigated the association of common polymorphisms of IGF-1, IGF-2, IGF-1 receptor, IGF binding protein-3, growth hormones (GH) 1 and GH2, and GH receptor with reflux esophagitis (RE), Barrett esophagus (BE), and EAC. Two hundred and thirty RE, 224 BE, 227 EAC cases, and 260 controls were studied. Gene polymorphisms were identified using publicly available online resources; 102 IGF axis tag and putatively functional single-nucleotide polymorphisms (SNPs) were analyzed using MassARRAY iPLEX and Taqman assays. Results were analyzed using Haploview. RESULTS Three polymorphisms were disease-associated. IGF1 SNP rs6214 was associated with BE (adjusted P = .039). Using GG genotype as reference, odds ratio for BE in AA (wild-type) was 0.43 (95% confidence interval [CI], 0.24-0.75). GH receptor SNP rs6898743 was associated with EAC (adjusted P = .0112). With GG as reference, odds ratio for EAC in CC (wild-type) genotype was 0.42 (95% CI, 0.23-0.76). IGF1 (CA)(17) 185-bp allele was associated with RE (adjusted P = .0116). Using IGF1(non17) as reference, odds ratio for RE in IGF1(17) carriers was 7.29 (95% CI, 1.57-46.7). CONCLUSIONS In this study, 3 polymorphisms of IGF genes were associated with EAC or its precursors. These polymorphisms may be markers of disease risk; independent validation of our findings is required. These results suggest the IGF pathway is involved in EAC development.
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Affiliation(s)
- Adrian R McElholm
- Cancer Epidemiology and Prevention Research Group, Centre for Public Health, Queens University of Belfast, Belfast, United Kingdom.
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Johansson M, McKay JD, Wiklund F, Rinaldi S, Hallmans G, Bälter K, Adami HO, Grönberg H, Stattin P, Kaaks R. Genetic variation in the SST gene and its receptors in relation to circulating levels of insulin-like growth factor-I, IGFBP3, and prostate cancer risk. Cancer Epidemiol Biomarkers Prev 2009; 18:1644-50. [PMID: 19423539 DOI: 10.1158/1055-9965.epi-08-0893] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Somatostatin (SST) and its receptors (SSTR1-5) may have a role in prostate cancer by influencing the IGFI hormone axis or through direct effects on prostate epithelia. We have investigated if genetic variation in the SST and SSTR1-5 genes influences prostate cancer risk and/or circulating IGFI and IGFBP3 hormone levels. MATERIALS AND METHODS We analyzed 28 haplotype tagging single nucleotide polymorphisms in the SST and SSTR1-5 genes in a case-control/genetic association study to investigate the association between genetic variation and prostate cancer risk. The study included 2863 cases and 1737 controls from the Cancer Prostate in Sweden (CAPS) study. To investigate the genetic influence on circulating hormone levels, plasma concentrations of IGFI and IGFBP3 were analyzed in 874 controls of the CAPS study and 550 male subjects from the Northern Sweden Health and Disease Cohort (NSHDC). RESULTS No clear association between prostate cancer risk and genetic variation of the SST and SSTR1-5 genes was identified. The SSTR5 missense single nucleotide polymorphism rs4988483 was associated with circulating IGFI (P = 0.002) and IGFBP3 (P = 0.0003) hormone levels in CAPS controls, with a per allele decrease of approximately 11%. This decrease was replicated in NSHDC for circulating IGFBP3 (P = 0.01) but not for IGFI (P = 0.09). Combining CAPS and NSHDC subjects indicated evidence of association between rs4988483 and both IGFBP3 (P = 2 x 10(-5)) and IGFI (P = 0.0004) hormone levels. CONCLUSIONS Our results suggest that genetic variation in the SSTR5 gene and, particularly, the rs4988483 single nucleotide polymorphism influence circulating IGFI and IGFBP3 hormone levels with no measurable effect on prostate cancer risk.
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Affiliation(s)
- Mattias Johansson
- International Agency For Research on Cancer, F-69372 Lyon Cedex 08, France
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Cao G, Lu H, Feng J, Shu J, Zheng D, Hou Y. Lung Cancer Risk Associated with Thr495Pro Polymorphism of GHR in Chinese Population. Jpn J Clin Oncol 2008; 38:308-16. [DOI: 10.1093/jjco/hyn007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Hahn NM, Kelley MR, Klaunig JE, Koch MO, Li L, Sweeney CJ. Constitutional polymorphisms of prostate cancer: prognostic and diagnostic implications. Future Oncol 2008; 3:665-82. [PMID: 18041919 DOI: 10.2217/14796694.3.6.665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Prostate cancer is the most common cancer diagnosis in men. While often perceived as a slow, indolent malignancy, prostate cancer trails only lung cancer among cancer-related mortality in men. Current diagnosis and treatment algorithms are plagued by overdiagnosis of non-lethal indolent prostate cancer with no proven means to predict, detect, and prevent aggressive lethal prostate cancer in men most at risk. These challenges are particularly concerning for African-American men who demonstrate increased rates of prostate cancer incidence and mortality when compared to other ethnic groups. With the completion of the human genome project, technology and techniques now exist to differentiate cancer from normal tissues based on the expression patterns of thousands of genes assessed simultaneously on a single microarray gene 'chip'. This platform has greatly improved our understanding of genes that regulate tumor behavior once cancer is established. Microarrays can also be utilized in patients without cancer to determine which patients are at high risk for tumor development and in need of rational prevention strategies. Constitutional single nucleotide polymorphisms (SNPs) are one source of genetic variation and may serve as a means to identify these high-risk individuals. SNPs are single nucleotide base pair changes within a gene which occur in one percent or more of the population. SNPs can contribute to a disease state by altering the function of a protein encoded by a gene without affecting gene expression. This review will examine the current understanding of constitutional SNPs associated with prostate cancer carcinogenesis, highlight two current diagnostic array platforms and discuss implications for future prevention and screening programs.
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Affiliation(s)
- Noah M Hahn
- Indiana University Melvin & Bren Simon Cancer Center, Indiana Cancer Pavilion Room RT415, 535 Barnhill Drive, Indianapolis, Indiana 46202, USA.
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Bibliography. Current world literature. Growth and development. Curr Opin Endocrinol Diabetes Obes 2008; 15:79-101. [PMID: 18185067 DOI: 10.1097/med.0b013e3282f4f084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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11
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Holly JM, Foulstone EJ, Perks CM. How growth hormone may be linked to cancer: concerns and perspective. Expert Rev Endocrinol Metab 2007; 2:759-771. [PMID: 30290467 DOI: 10.1586/17446651.2.6.759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent evidence from epidemiology indicates that inter-individual variations in the growth hormone (GH)/IGF-I pathway affect the risk of individuals developing common epithelial cancers. This is supported by associations between normal common variants within genes from the pathway and these cancers, which excludes many potential confounding issues, such as reverse causality. This raises concern for the increasing numbers of patients treated with GH; although replacement therapy for GH-deficiency should aim to restore normality, which should then only incur a normal risk. The links with cancer also offers promising new opportunities. Clinical trials treating cancer patients with pharmaceuticals targeting the IGF-I receptor are well advanced with promising initial findings. In the future, there has to be much more emphasis within oncology on prevention and the GH/IGF-I pathway is one of few identified risk factors that are modifiable, not just by pharmaceutical, but also nutritional, interventions that may, in the long term, be more appropriate. Assessing the status of the GH/IGF-I pathway in individuals may also provide a means for targeting screening programs and preventative measures.
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Affiliation(s)
- Jeff Mp Holly
- a University of Bristol, Department of Clinical Science at North Bristol, Paul O'Gorman Lifeline Centre, Southmead Hospital, Bristol BS10 5NB, UK.
| | - Emily J Foulstone
- a University of Bristol, Department of Clinical Science at North Bristol, Paul O'Gorman Lifeline Centre, Southmead Hospital, Bristol BS10 5NB, UK.
| | - Claire M Perks
- a University of Bristol, Department of Clinical Science at North Bristol, Paul O'Gorman Lifeline Centre, Southmead Hospital, Bristol BS10 5NB, UK.
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Strawbridge RJ, Kärvestedt L, Li C, Efendic S, Ostenson CG, Gu HF, Brismar K. GHR exon 3 polymorphism: association with type 2 diabetes mellitus and metabolic disorder. Growth Horm IGF Res 2007; 17:392-398. [PMID: 17537658 DOI: 10.1016/j.ghir.2007.04.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Revised: 03/16/2007] [Accepted: 04/10/2007] [Indexed: 11/23/2022]
Abstract
Growth hormone (GH) signaling via the growth hormone receptor (GHR) forms a major part of the GH-IGF-I axis, which is crucial for controlling metabolism and anabolism. Two common variants of the GHR differ by the presence (full length or GHR(fl)) or absence of exon 3 (exon 3 deleted or GHR(d3)), the function of which is unknown. However, differential response to GH treatment has been observed with carriers of the GHR(d3) variant conferring a greater growth rate. This study investigates these GHR variants in subjects with normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), including Type 2 diabetes mellitus (T2DM). DNA was extracted from blood samples from subjects with NGT (n=158), IGT (n=116) and T2DM (n=194). The T2DM subjects in set 1 (n= 39) were newly diagnosed, whilst those in set 2 (n=155) had a mean duration of 7 years. Set 1 also included NGT and IGT subjects. Genotyping by standard PCR and gel electrophoresis were carried out. A significant difference was observed between T2DM and NGT (p<0.0001) with a significantly lower frequency of GHR(d3) in T2DM (3.6% compared to 17% in NGT). Both sets of T2DM subjects with at least one GHR(d3) allele had significantly higher BMI. In the larger subset of T2DM, GHR(d3) was associated with higher CRP levels as well as age adjusted IGF-I, with a trend of higher C-peptide secretion and impaired lipid levels, indicating a phenotype with metabolic disorder when compared to the GHR(fl/fl) T2DM subjects. In conclusion, homozygosity for the GHR(d3) allele appears to be preventive of T2DM. However, when other factors cause overt T2DM, the GHR(d3) allele confers a phenotype indicative of metabolic disorder. This study supports the hypothesis that the two GHR alleles by their inclusion or exclusion of exon 3 are functionally different.
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Affiliation(s)
- R J Strawbridge
- Department of Oncology Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Solna, 171 76 Stockholm, Sweden.
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