[Single nucleotide polymorphism of IL-23 receptor gene is associated with susceptibility to recurrent oral ulceration]

Objective To explore whether single nucleotide polymorphism (SNP) in interleukin-23 receptor (IL-23R) gene is associated with the susceptibility to recurrent oral ulceration (ROU). Methods The genotype of SNP rs11465817 and rs1343152 was determined by MALDI-TOF-MS in 42 ROU patients and 86 age- and sex-matched healthy controls. The genotype and allele frequencies were analyzed by Chi-square test in both groups. Odds ratio (OR) and 95% confidence interval (95%CI) were calculated to analyze the associations between the susceptibility of ROU and the genotypes. Results The rs1343152 allele and genotype frequency distribution had no significantly difference between the case group and the control group. Compared with the control group, rs11465817 allele and genotype frequency distribution in the ROU group had significant difference (OR=2.715, 95%CI=1.543-4.777). The AA+AC genotype increased the risk of ROU occurrence by 2.44 times. Conclusion IL-23R rs11465817 contributes to the risk of ROU in Chinese.

The promise of discovering population-specific disease-associated genes in South Asia

The more than 1.5 billion people who live in South Asia are correctly viewed not as a single large population but as many small endogamous groups. We assembled genome-wide data from over 2,800 individuals from over 260 distinct South Asian groups. We identified 81 unique groups, 14 of which had estimated census sizes of more than 1 million, that descend from founder events more extreme than those in Ashkenazi Jews and Finns, both of which have high rates of recessive disease due to founder events. We identified multiple examples of recessive diseases in South Asia that are the result of such founder events. This study highlights an underappreciated opportunity for decreasing disease burden among South Asians through discovery of and testing for recessive disease-associated genes.

Correlations of Galectin-3 Gene Polymorphisms with Risk and Prognosis of Cervical Cancer in Chinese Populations: A Case-Control Study

BACKGROUND

This study explores correlations of galectin-3 gene polymorphisms (rs4644, rs4652, and rs11125) with cervical cancer risk and prognosis in Chinese populations.

METHODS

A total of 126 patients with cervical cancer were selected to form the case group, and 102 healthy people were selected for the control group following a physical examination. 3 polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

The distribution frequencies of the CC+CA genotype of rs4652 and the AT+TT genotype of rs11125 in the case group were remarkably higher than those in the control group. rs4644 only had correlations with tumor diameter, while rs4652 and rs11125 had correlations with tumor diameter, FIGO staging, differentiation grades, clinical staging, lymph node metastasis (LNM), and treatment modality. The 5-years survival rate of patients with CC+CA of rs4652 was lower but the recurrence rate was higher compared to AA type patients. In contrast, AA type patients with rs11125 had a higher 5-year survival rate but a lower recurrence rate than those of AT+TT type. CC+CA genotype of rs4652, AT+TT genotype of rs11125, and treatment modality were independent factors related to overall survival and disease-free survival, and LNM was an independent factor related to OS.

CONCLUSION

Our findings provide evidence that allele C of rs4652 and allele T of rs11125 in the galectin-3 gene may be risk factors for cervical cancer.

Association of CYP1A1 and CYP1B1 polymorphisms with bone mineral density variations in postmenopausal Mexican-Mestizo women

Herein, we investigated potential associations between polymorphisms of genes related to estrogen metabolism and bone mineral density (BMD) in postmenopausal women. This was a cross-sectional study, in which two hundred and ninety postmenopausal Mexican-Mestizo women were studied. The BMD of the lumbar spine (LS), total hip (TH), and femoral neck (FN) was measured. The distribution of the genetic polymorphisms, including rs1799814 and rs1048943 at CYP1A1 as well as rs1056836 at CYP1B1, were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), single-stranded conformational polymorphism (SSCP), and DNA sequencing. Deviations from Hardy-Weinberg equilibrium (HWE) were tested, and linkage disequilibrium (LD) was calculated by direct correlation (r²). Moreover, haplotype analysis was performed. All polymorphisms were in HWE. The genotype and allele distributions of the three single nucleotide polymorphisms (SNPs) studied showed no significant differences. However, statistical significance was reached when constructing haplotypes. The CG haplotype in CYP1A1 was associated with variations in LS and FN BMD after adjustment for covariates (p = 0.021 and 0.045, respectively), but the association with TH BMD was not significant. These results suggested that the CG haplotype in CYP1A1 may play an important role in the mechanism of osteoporosis and may be useful as a genetic marker.

Association between polymorphisms in pre-miRNA genes and risk of oral squamous cell cancer in a Chinese population

Background

MicroRNAs play important roles in the development of human cancers. This case-control study is to evaluate the roles of the polymorphisms in pre-miRNAs on risk of oral cancer in a Chinese population.

Methods

The genotypes of three polymorphisms were determined in 340 patients with oral squamous cell cancer and 340 healthy controls who were frequency matched for age and sex. Odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated to assess the association. All analyses were performed using the SPSS software. 3.154() 0.001.

Results

For miR-499 rs3746444, individuals carrying homozygous CC genotype had increased risks of oral cancer compared with the homozygous wild TT genotype (adjusted OR was 3.154, 95%CI was 1.555–6.397, P value was 0.001). The C allele of miR-499 rs3746444 was associated with a higher risk of oral cancer with significant odds ratio of 1.453. In the stratified analyses by sex, the associations between miR-499 rs3746444 and miR-146a rs2910164 polymorphisms with the susceptibility of oral squamous cell cancer were significant in males. However, with 1/4 as many subjects there were no significant associations between the three polymorphisms and oral cancer risks in females. The joint effects of miRNA polymorphisms and smoking on the risk of OSCC were analyzed and the results suggested that the association between microRNA genetic variants and OSCC risk was modified by smoking.

Conclusions

These findings suggest that miR-499 rs3746444 and miR-146a rs2910164 polymorphisms may contribute to genetic susceptibility to oral squamous cell cancer.

A novel polymorphism in protein kinase AMP-activated catalytic subunit alpha 2 (PRKAA2) is associated with type 2 diabetes in the Han Chinese population

BACKGROUND

It has been proposed that the energy-sensing enzyme AMP-activated protein kinase (AMPK) is a key agent in the pathophysiology of type 2 diabetes mellitus (T2DM). The gene encoding protein kinase AMP-activated catalytic subunit alpha 2 (PRKAA2) is located at one of the Asian T2DM loci (1p32). Therefore, the aim of the present study was to test for the association of common variants in PRKAA2 with T2DM in the Han Chinese population.

METHODS

We genotyped 221 T2DM patients and 111 controls to assess possible associations of two tagging single nucleotide polymorphisms (tSNPs) in the PRKAA2 gene with T2DM.

RESULTS

The clinical characteristics of T2DM cases compared with controls differed significantly. No significant association was observed with the rs2143754 polymorphism whereas the rs2746342 polymorphism exhibited a highly significant association with T2DM. Fasting plasma glucose (FPG) of subjects carrying the G/G genotype of the rs2746342 polymorphism was higher than that of subjects carrying the T allele (P = 0.0049). These associations were magnified in the presence of the G/G genotype of the rs2143754 polymorphism.

CONCLUSIONS

The rs2746342 polymorphism is significantly associated with susceptibility to T2DM and seems to interact with the rs2143754 polymorphism in the modulation of FPG in the Han Chinese population.

Risk prediction of pulmonary tuberculosis using genetic and conventional risk factors in adult Korean population

A complex interplay among host, pathogen, and environmental factors is believed to contribute to the risk of developing pulmonary tuberculosis (PTB). The lack of replication of published genome-wide association study (GWAS) findings limits the clinical utility of reported single nucleotide polymorphisms (SNPs). We conducted a GWAS using 467 PTB cases and 1,313 healthy controls obtained from two community-based cohorts in Korea. We evaluated the performance of PTB risk models based on different combinations of genetic and nongenetic factors and validated the results in an independent Korean population comprised of 179 PTB cases and 500 healthy controls. We demonstrated the polygenic nature of PTB and nongenetic factors such as age, sex, and body mass index (BMI) were strongly associated with PTB risk. None of the SNPs achieved genome-wide significance; instead, we were able to replicate the associations between PTB and ten SNPs near or in the genes, CDCA7, GBE1, GADL1, SPATA16, C6orf118, KIAA1432, DMRT2, CTR9, CCDC67, and CDH13, which may play roles in the immune and inflammatory pathways. Among the replicated SNPs, an intergenic SNP, rs9365798, located downstream of the C6orf118 gene showed the most significant association under the dominant model (OR = 1.59, 95% CI 1.32–1.92, P = 2.1×10⁻⁶). The performance of a risk model combining the effects of ten replicated SNPs and six nongenetic factors (i.e., age, sex, BMI, cigarette smoking, systolic blood pressure, and hemoglobin) were validated in the replication set (AUC = 0.80, 95% CI 0.76–0.84). The strategy of combining genetic and nongenetic risk factors ultimately resulted in better risk prediction for PTB in the adult Korean population.

Study and evaluation the impact of vitamin D receptor variants on the risk of type 2 diabetes mellitus in Han Chinese

BACKGROUND

Vitamin D and the vitamin D receptor (VDR) are associated with susceptibility to type 2 diabetes mellitus (T2DM). The purpose of the present study was to screen more single nucleotide polymorphisms (SNPs) of VDR and assess their effects on the risk of T2DM in Han Chinese.

METHOD

Four SNPs were genotyped in 1191 individuals (397 cases, 794 controls). Allele frequencies and genotype distributions were analyzed. Effects were investigated by evaluating genotype distribution with regard to phenotypes, insulin resistance, and β-cell function. Haplotype analysis and gene risk score (GRS) were used to evaluate the combined and additive roles of VDR SNPs on T2DM pathogenesis.

RESULTS

There was a significant association between rs739837 and T2DM in two models and allele frequency distribution. The novel locus rs2239179 differed significantly between cases and controls, especially in males and those aged >55 years, in three models and allele frequency distribution. The TT genotype of rs739837 was associated with higher triglyceride than GG and TG genotypes, and higher total cholesterol levels than the GG genotype. Compared with the GTGA haplotype, the GCGG haplotype reduced the risk of T2DM. Trend Chi-squared tests showed that there was significant association between the weighted GRS and the risk of T2DM (P_trend  = 0.034).

CONCLUSION

This study provides novel evidence that rs739837 is associated with lipid metabolism in T2DM patients. The rs739837 and rs2239179 SNPs were associated with the risk of T2DM in Han Chinese. The VDR SNPs had combined and additive effects on the risk of T2DM.

Rare variants in fox-1 homolog A (RBFOX1) are associated with lower blood pressure

Many large genome-wide association studies (GWAS) have identified common blood pressure (BP) variants. However, most of the identified BP variants do not overlap with the linkage evidence observed from family studies. We thus hypothesize that multiple rare variants contribute to the observed linkage evidence. We performed linkage analysis using 517 individuals in 130 European families from the Cleveland Family Study (CFS) who have been genotyped on the Illumina OmniExpress Exome array. The largest linkage peak was observed on chromosome 16p13 (MLOD = 2.81) for systolic blood pressure (SBP). Follow-up conditional linkage and association analyses in the linkage region identified multiple rare, coding variants in RBFOX1 associated with reduced SBP. In a 17-member CFS family, carriers of the missense variant rs149974858 are normotensive despite being obese (average BMI = 60 kg/m2). Gene-based association test of rare variants using SKAT-O showed significant association with SBP (p-value = 0.00403) and DBP (p-value = 0.0258) in the CFS participants and the association was replicated in large independent replication studies (N = 57,234, p-value = 0.013 for SBP, 0.0023 for PP). RBFOX1 is expressed in brain tissues, the atrial appendage and left ventricle in the heart, and in skeletal muscle tissues, organs/tissues which are potentially related to blood pressure. Our study showed that associations of rare variants could be efficiently detected using family information.

ALKBH7 Variant Related to Prostate Cancer Exhibits Altered Substrate Binding

The search for prostate cancer biomarkers has received increased attention and several DNA repair related enzymes have been linked to this dysfunction. Here we report a targeted search for single nucleotide polymorphisms (SNPs) and functional impact characterization of human ALKBH family dioxygenases related to prostate cancer. Our results uncovered a SNP of ALKBH7, rs7540, which is associated with prostate cancer disease in a statistically significantly manner in two separate cohorts, and maintained in African American men. Comparisons of molecular dynamics (MD) simulations on the wild-type and variant protein structures indicate that the resulting alteration in the enzyme induces a significant structural change that reduces ALKBH7’s ability to bind its cosubstrate. Experimental spectroscopy studies with purified proteins validate our MD predictions and corroborate the conclusion that this cancer-associated mutation affects productive cosubstrate binding in ALKBH7.

Improvements in personalized DNA sequencing have led to an increased interest in targeted biomarkers for therapeutic and diagnostic purposes. In this work, we report on a new biomarker for prostate cancer found through a targeted search for single nucleotide polymorphisms (SNPs) of the genes encoding human ALKBH family dioxygenases. Our results uncovered rs7540, which leads to a missense mutation in ALKBH7. Comparative molecular dynamics simulations on the wild type and SNP variant of the protein show that the mutation elicits a structural change that dramatically decreases ALKBH7’s affinity for its cosubstrate. This prediction is confirmed by experimental UV-Vis spectroscopy. Taken together, these results give important insights into a novel prostate-cancer related SNP and its impact on the structure and function of ALKBH7.

Generalization and fine mapping of European ancestry-based central adiposity variants in African ancestry populations

BACKGROUND/OBJECTIVES

Central adiposity measures such as waist circumference (WC) and waist-to-hip ratio (WHR) are associated with cardiometabolic disorders independently of body mass index (BMI) and are gaining clinically utility. Several studies report genetic variants associated with central adiposity, but most utilize only European ancestry populations. Understanding whether the genetic associations discovered among mainly European descendants are shared with African ancestry populations will help elucidate the biological underpinnings of abdominal fat deposition.

SUBJECTS/METHODS

To identify the underlying functional genetic determinants of body fat distribution, we conducted an array-wide association meta-analysis among persons of African ancestry across seven studies/consortia participating in the Population Architecture using Genomics and Epidemiology (PAGE) consortium. We used the Metabochip array, designed for fine-mapping cardiovascular-associated loci, to explore novel array-wide associations with WC and WHR among 15 945 African descendants using all and sex-stratified groups. We further interrogated 17 known WHR regions for African ancestry-specific variants.

RESULTS

Of the 17 WHR loci, eight single-nucleotide polymorphisms (SNPs) located in four loci were replicated in the sex-combined or sex-stratified meta-analyses. Two of these eight independently associated with WHR after conditioning on the known variant in European descendants (rs12096179 in TBX15-WARS2 and rs2059092 in ADAMTS9). In the fine-mapping assessment, the putative functional region was reduced across all four loci but to varying degrees (average 40% drop in number of putative SNPs and 20% drop in genomic region). Similar to previous studies, the significant SNPs in the female-stratified analysis were stronger than the significant SNPs from the sex-combined analysis. No novel associations were detected in the array-wide analyses.

CONCLUSIONS

Of 17 previously identified loci, four loci replicated in the African ancestry populations of this study. Utilizing different linkage disequilibrium patterns observed between European and African ancestries, we narrowed the suggestive region containing causative variants for all four loci.

Cancer Risk Information Sharing: The Experience of Individuals Receiving Genetic Counseling for BRCA1/2 Mutations

Genetic counseling and testing for familial cancer is a unique context for the communication of risk information in the family. This study utilized a theoretical framework based on the family systems perspective to understand intrafamilial cancer risk communication patterns in the Ashkenazi Jewish population. Individuals (n = 120) at an elevated risk for BRCA1/2 mutations were included. Change in communication patterns over time was assessed using McNemar tests. Associations with communication patterns were assessed with multivariable logistic regression. Overall, the proportion of participants encouraged by others significantly (p < .001) increased from before to after genetic counseling. A higher proportion of participants were encouraged by female family members compared with male family members. Participants who were older, had no personal history of cancer, and had a higher cancer risk perception were more likely to be encouraged by others for genetic testing. Participant's intent to encourage family members for genetic testing from before counseling to after receipt of genetic test results decreased by 16.7%. Participants who had no personal history of cancer and had informative test results for a BRCA1/2 mutation were more likely to encourage other family members for genetic testing. In addition, qualitative findings suggested that closeness among family members, concern for family, especially future generations, and cognizance about cancer risk facilitate information sharing and encouragement for genetic testing. Our findings indicate that intrafamilial cancer risk communication varies with the structure of family relationships and that genetic counseling can play an important role in improving intrafamilial cancer risk communication.

The Lack of Association between FCN2 Gene Promoter Region Polymorphisms and Dental Caries in Polish Children

The aim of this study was to examine the association of single-nucleotide polymorphisms (SNPs) in the gene encoding ficolin-2 protein (FCN2 gene) at positions -986 (rs17514136), -602 (rs3124953), and -4 (rs3124952) with dental caries in Polish children. Two hundred and sixty Polish Caucasian children aged 15 years were enrolled in this study: 82 with "higher" caries experience (DMFT >5) and 178 with "lower" caries experience (DMFT ≤5). In addition, subjects with caries experience (DMFT ≥1) and caries-free subjects (DMFT = 0) were compared. FCN2 SNPs were genotyped with PCR-RFLP methods. There were no significant differences in the genotype, allele, or haplotype distributions in 3 analyzed SNPs of the FCN2 gene between children with "higher" and those with "lower" caries experience as well as between children with caries experience and caries-free children. In conclusion, we did not find any association of FCN2 promoter polymorphisms at positions -986, -602, and -4 with dental caries in Polish children.

Protective effects of an HTRA1 insertion-deletion variant against age-related macular degeneration in the Chinese populations

Age-related macular degeneration (AMD) is a leading cause of visual impairment and irreversible blindness in most developed countries, affecting about 50 million elderly people worldwide. Retinal pigment epithelial (RPE) cell degeneration is the pathophysiological cause of AMD, leading to geographic atrophy and choroidal neovascularization. We and others have previously identified several polymorphisms on chromosome 10q26 (HTRA1 rs11200638 as well as LOC387715 rs10490924 and c.372_815del443ins54) associated with AMD. In this study, we confirmed the association of our previously identified HTRA1 insertion-deletion (indel) variant (c.34delCinsTCCT) in 195 exudative AMD patients and 390 controls from the Hong Kong Chinese cohort with additional 168 patients and 210 controls from the Chengdu Chinese cohort and followed by studying its biological functions in RPE cells. Genetic analysis verified the higher prevalence of c.34delCinsTCCT allele in control subjects (8.0%) than in AMD patients (1.9%; P=7.87 × 10-5, odds ratio=0.229). This protective effect was validated as the haplotype of the c.34delCinsTCCT allele existed independent of the risk haplotype (P=1.17 × 10-5). In vitro studies showed that recombinant HTRA1 c.34delCinsTCCT variant protein was more localized in the endoplasmic reticulum of RPE cells compared with the wild-type protein, and its secretion was delayed. Moreover, ARPE-19 cells expressing HTRA1 c.34delCinsTCCT variant had higher cell viability, lower cell apoptosis and were less responsive to anoikis, supporting its protective role. We revealed a protective AMD-associated HTRA1 variant in Chinese populations and the biological role of HTRA1 in RPE cell degeneration, indicating its involvement in AMD pathogenesis.

Sharing results from complex disease genetics studies: a community based participatory research approach

OBJECTIVES

Dissemination of research results to communities builds capacity of the community to understand and utilize the results. The objective of this manuscript was to propose a culturally appropriate approach to disseminate complex disease genetics research findings in small Alaska Native communities.

STUDY DESIGN

The Center for Alaska Native Health Research is a community-based participatory research project (CBPR) directed at understanding the interactions between genetic, nutritional and psychosocial risk factors for obesity, diabetes, and cardiovascular disease in Yup'ik Eskimos.

METHODS

We have consulted with regional healthcare providers, tribal leaders, and university-, local-, and national-institutional review boards to identify potential mechanisms for sharing population-based genetics research results or progress.

RESULTS

We propose a six step CBPR-approach to conducting genetics research in isolated identifiable communities. This CPBR-approach includes generating a common research question, determining community interest, recruitment, capacity building, sharing power and control, avoiding group harm, and development of culturally appropriate dissemination procedures.

CONCLUSIONS

Research scientists and community members should both benefit from population-based genetics research. Although we are just beginning our discussions with regard to sharing genetics research progress and findings, we believe that it is essential move forward as co-researchers in the CBPR enterprise.

Heterozygote Advantage of the rs3794624 Polymorphism in CYBA for Resistance to Tuberculosis in Two Chinese Populations

Phagocyte Nicotinamide Adenine Dinucleotide Phosphate (NADPH) oxidase complex is a key enzyme that catalyzes the production of reactive oxygen species, which mediate oxygen-dependent killing of microorganisms, such as Mycobacterium tuberculosis. P22phox, encoded by CYBA, is the key regulatory subunit of NADPH oxidase. Our study aimed to investigate the association of CYBA polymorphisms with susceptibility to tuberculosis. Three SNPs (rs9932581, rs3794624 and rs4673) were genotyped in the discovery cohort composed of Chinese Han individuals. We found that the A allele of rs3794624 was a significant protective factor against tuberculosis (GA vs. GG: OR = 0.74, 95% CI 0.57-0.96; GA vs. GG+AA: OR = 0.73, 95% CI 0.56-0.95), which was then replicated in the Chinese Tibetan population (GA vs. GG: OR = 0.68, 95% CI 0.51-0.92; AA+GA vs. GG: OR = 0.70, 95% CI 0.52-0.93; GA vs. GG+AA: OR = 0.68, 95% CI 0.51-0.92). Meta-analysis including both cohorts identified overdominance as the best genetic model and provided robust evidence for the protective effect of the rs3794624 GA genotype against tuberculosis without any evidence of heterogeneity (GA vs. GG+AA: OR = 0.71, 95% CI 0.58-0.86). Our study found an association between the GA genotype of rs3794624 in CYBA with decreased tuberculosis susceptibility in two Chinese populations. Further analyses are needed to reveal the potential function of this SNP.

[Analysis of COL1A1 gene mutation in an ethnic Han Chinese family from Henan affected with osteogenesis imperfecta]

OBJECTIVE

To identify potential mutation of COL1A1 gene in an ethnic Han Chinese family from Henan affected with osteogenesis imperfecta (OI).

METHODS

Peripheral blood samples were collected from all 11 members of the family and 50 healthy adults for the extraction of genomic DNA. All exons and introns of the COL1A1 gene were amplified by polymerase chain reaction and subjected to direct sequencing. Mutations found in the proband were analyzed through comparison with other members of the family, 50 healthy individuals and sequence from the GenBank.

RESULTS

Fifteen sequence variants were discovered, which included 1 missense mutation, 1 synonymous mutation and 13 intronic mutations. All of the 4 patients from the family were detected as having carried a novel heterozygous missense mutation (c.4193T>G, p.I1398S) in exon 50 of the COL1A1 gene. The father of the proband has carried the same mutation but had a normal phenotype. The same mutation was not found in other healthy members of the family.

CONCLUSION

The OI type of this family may have been autosomal dominant with incomplete penetrance or autosomal recessive associated with COL1A1 gene mutations.

[Novel missense mutations of the FLG gene identified in two Chinese families affected with ichthyosis vulgaris]

OBJECTIVE

To identify potential mutations of the FLG gene in two Chinese families affected with ichthyosis vulgaris.

METHODS

All coding exons and exon-intron boundary of the FLG gene were amplified by polymerase chain reaction (PCR) and analyzed by direct sequencing. The results were compared with those of 100 unrelated healthy controls.

RESULTS

Two novel missense mutations, c.1360A>G (p.T454A) and c.10363G>T (p.D3455Y), were detected in all affected individuals from family 1 and family 2 respectively but none of the controls.

CONCLUSION

The c.1360A>G (p.T454A) and c.10363G>T (p.D3455Y) of the FLG gene may lead to alteration of the structure and function of the FLG protein and cause ichthyosis vulgaris in the two families.

[Mutation analysis for a large Chinese family affected with MYH9-related thrombocytopenia]

OBJECTIVE

To analyze the clinical manifestations and mutation of MYH9 gene in a large Chinese family affected with MYH9-related thrombocytopenia.

METHODS

After informed consent was obtained; clinical examination and history investigation was performed on 29 members of the family. DNA was extracted using a standard method, then exons 1 to 40 and their corresponding exon-intron junctions of the MYH9 gene were amplified with PCR and subjected to Sanger sequencing. The results were compared to reference sequence from the University of California, Santa Cruz (UCSC) to screen the mutation. PCR and Sanger sequencing was performed on genome DNA of all family members to confirm the identified mutation.

RESULTS

The clinical manifestations of family members were prominently heterogeneous. Four affected members showed hearing loss or deafness, two affected members showed nephritis or kidney failure, and other affected members was only characterized by mild bleeding or with no obvious symptoms. A heterozygous missense mutation c.4270G>A (p.Aspl841Asn) in exon 30 of the MYH9 gene was identified in all affected members from this family, which also co-segregated with the phenotype.

CONCLUSION

A missense mutation c.4270G>A (p.Aspl841Asn) within the exon 30 of the MYH9 gene was identified to be associated with MYH9-related thrombocytopenia in a Chinese family.

Predictors of Self-Reported Family Health History of Breast Cancer

The objective of this study was to identify predictors of self-reported family health history of breast cancer in an ethnically diverse population of women participating in a breast cancer screening program. Participants completed a self-administered questionnaire about their demography, health, breast health and family health history of breast cancer. The association between family health history of breast cancer and categorical variables were analyzed using the T test, chi square, and multi-nominal logistic regression. Those who were least likely to report a family history of cancer were African Americans (p = 0.02), and immigrant women from South America (p < 0.001) and Africa (p = 0.04). However, 34.4 % reported having a second-degree maternal relative with breast cancer compared to 6.9 % who reported having a second degree paternal relative with breast cancer. Therefore, there is a need to increase efforts to educate families about the importance of collecting and sharing one's family health history.

Variant of the clock circadian regulator (CLOCK) gene and related haplotypes are associated with the prevalence of type 2 diabetes in the Japanese population

BACKGROUND

Circadian rhythm disruptions can cause various health disorders. The present study evaluated associations between single nucleotide polymorphisms in the core circadian gene clock circadian regulator (CLOCK) and the prevalence of type 2 diabetes (T2D) in the Japanese population.

METHODS

Cross-sectional data were analyzed from 2485 subjects (1243 men, 1242 women; age 35-69 years) enrolled in the baseline surveys of the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study. Associations between three CLOCK gene polymorphisms (rs1801260, rs3736544, and rs4864548) and the prevalence of obesity (body mass index [BMI] ≥25 kg/m(2) ), overweight (BMI ≥23 kg/m(2) ), and T2D were evaluated by logistic regression analyses; haplotype analysis and stratified analyses for the prevalence of diabetes were also conducted.

RESULTS

Compared with those who were homozygous for the respective major alleles, subjects with the rs1801260 minor allele C had a significantly higher odds ratio (1.5; 95% confidence interval 1.1-2.1) for the prevalence of diabetes after adjustment for potential confounding factors, including BMI. When stratified by overweight, the associations between rs1801260 and the prevalence of diabetes were marked and significant in non-overweight subjects, but not in overweight subjects. The TGA (rs1801260-rs3736544-rs4864548) haplotype was associated with a lower prevalence of diabetes, whereas the CGG haplotype was associated with a higher prevalence of diabetes.

CONCLUSIONS

Variant of the CLOCK gene and related haplotypes are associated with the prevalence of T2D in the Japanese population, in which obesity is less common, and the association between CLOCK gene variant at rs1801260 and the prevalence of diabetes is enhanced in normal-weight subjects.

Genetic Variation of Methylenetetrahydrofolate Reductase (MTHFR) and Thymidylate Synthase (TS) Genes Is Associated with Idiopathic Recurrent Implantation Failure

The one-carbon metabolism pathway disorder was important role in successful pregnancy. The MTHFR and TS protein were crucial factor in one-carbon metabolism. To investigate the association between recurrent implantation failure (RIF) and enzymes in the one-carbon metabolism pathway. A total of 120 women diagnosed with RIF and 125 control subjects were genotyped for MTHFR 677C>T, 1298A>C, TSER 2R/3R and TS 1494del/ins by a polymerase chain reaction-restriction fragment length polymorphism assay. According to the gene-gene combination analysis, the MTHFR 677/MTHFR 1298 (TT/AA) and MTHFR 677/TS 1494 (TT/6bp6bp) genetic combinations were associated with relatively higher risks [adjusted odds ratio (AOR), 2.764; 95% CI, 1.065–7.174; P = 0.037 and AOR, 3.186; 95% CI, 1.241–8.178; P = 0.016] in RIF patients compared to the CC/AA (MTHFR 677/MTHFR 1298) and TT/6bp6bp (MTHFR 677/TS 1494) combinations, respectively. The results suggested that the combined MTHFR 677/MTHFR 1298 genotype might be associated with increased risk of RIF. To the best of our knowledge, this study is the first to elucidate the potential association of MTHFR, TS and TSER polymorphisms with RIF risk in Korean patients.

[Correlation between the genetic polymorphisms of apolipoprotein M with the susceptibility to rheumatic diseases of Chinese Han populastion in Lanzhou]

Objective To investigate the relationship between the genetic polymorphisms of apolipoprotein M (ApoM) and the susceptibility to rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and ankylosing spondylitis (AS) among Chinese Han population in Lanzhou. Methods Primers for the two single nucleotide polymorphism (SNP) sites (rs805296 and rs805297) in ApoM gene were designed and their genotyping methods of polymerase chain reaction-high resolution melting (PCR-HRM) assay were established. Case-control studies were performed among the 599 cases of RA, 194 cases of SLE, 179 cases of AS and 273 matched healthy controls to analyze the correlations between the two SNPs and the susceptibility to rheumatic diseases. Results The genotype frequencies of rs805296 were AA 87.0%, AG 12.7%, GG 0.3% in RA cases, AA 84.5%, AG 15.0%, GG 0.5% in SLE cases, AA 91.6%, AG 7.3%, GG 1.1% in AS cases, AA 85.0%, AG 15.0%, GG 0% in healthy controls. The ones of rs805297 were GG 38.2%, GT 51.8%, TT 10.0% in RA cases, GG 44.3%, GT 45.4%, TT 10.3% in SLE cases, GG 37.4%, GT 47.5%, TT 15.1% in AS cases, GG 40.7%, GT 46.1%, TT 13.2% in healthy controls. Statistical analyses showed that only the genotype distribution of rs805296 was significantly different between the AS cases and the healthy controls. Under the dominant model, the G allele carriers of rs805296 (AG heterozygote and GG homozygote) were found to significantly decrease the risk for AS development. Conclusion The established PCR-HRM genotyping assays in the present study can successfully achieve the molecular diagnosis of the two SNPs sites (rs805296 and rs805297) from clinical samples, and the study found a significant association between the SNP of rs805296 and the susceptibility to AS among Chinese Han population in Lanzhou.

Clinical features of Hispanic thyroid cancer cases and the role of known genetic variants on disease risk

Thyroid cancer (TC) is the second most common cancer among Hispanic women. Recent genome-wide association (GWA) and candidate studies identified 6 single nucleotide polymorphisms (SNPs; rs966423, rs2439302, rs965513, rs6983267, rs944289, and rs116909374), associated with increased TC risk in Europeans but their effects on disease risk have not been comprehensively tested in Hispanics. In this study, we aimed to describe the main clinicopathological manifestations and to evaluate the effects of known SNPs on TC risk and on clinicopathological manifestations in a Hispanic population.We analyzed 281 nonmedullary TC cases and 1146 cancer-free controls recruited in a multicenter population-based study in Colombia. SNPs were genotyped by Kompetitive allele specific polymerase chain reaction (KASP) technique. Association between genetic variants and TC risk was assessed by computing odds ratios (OR) and confidence intervals (CIs).Consistent with published data in U.S. Hispanics, our cases had a high prevalence of large tumors (>2 cm, 43%) and a high female/male ratio (5:1). We detected significant associations between TC risk and rs965513A (OR = 1.41), rs944289T (OR = 1.26), rs116909374A (OR = 1.96), rs2439302G (OR = 1.19), and rs6983267G (OR = 1.18). Cases carried more risk alleles than controls (5.16 vs. 4.78, P = 4.8 × 10). Individuals with ≥6 risk alleles had >6-fold increased TC risk (OR = 6.33, P = 4.0 × 10) compared to individuals with ≤2 risk alleles. rs944289T and rs116909374A were strongly associated with follicular histology (ORs = 1.61 and 3.33, respectively); rs2439302G with large tumors (OR = 1.50); and rs965513A with regional disease (OR = 1.92).To our knowledge, this is the first study of known TC risk variants in South American Hispanics and suggests that they increase TC susceptibility in this population and can identify patients at higher risk of severe disease.

Socioeconomic status in systemic lupus erythematosus

Our understanding of the biological pathogenesis of systemic lupus erythematosus (SLE) is rapidly expanding. Although biologic research is vital, studies that address the importance of socioeconomic factors that contribute to the causation of the outcome of SLE are necessary to understand the full scope of the disease.

Studies of social factors in SLE usually include ethnicity, gender and socioeconomic status (SES) as categorical variables. One hypothesis is that these variables exert their effect through a biologic or genetic factor. However, there is growing evidence to suggest a more direct psychological or sociological impact of these variables on disease. Although in research studies it may be difficult to tease out the biological and sociological impacts of these variables, the eventual understanding of these diverse roles will help in the design of eventual therapeutic interventions.

HTRA1 promoter variant differentiates polypoidal choroidal vasculopathy from exudative age-related macular degeneration

Exudative age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) share similar abnormal choroidal vasculature, but responses to treatments are different. In this study, we sequenced the whole HTRA1 gene and its promoter by direct sequencing in a Hong Kong Chinese PCV cohort. We identified rs11200638, c.34delCinsTCCT, c.59C>T, rs1049331 and rs2293870 significantly associated with PCV. Notably, rs2672598 was significantly associated with exudative AMD (p = 1.31 × 10(-4)) than PCV (p = 0.11). Logistic regression indicated that rs2672598 (p = 2.27 × 10(-3)) remained significant after adjusting for rs11200638 in exudative AMD. Moreover, the rs11200638-rs2672598 joint genotype AA-CC conferred higher risk to exudative AMD (43.11 folds) than PCV (3.68 folds). Promoter analysis showed that rs2672598 C-allele showed higher luciferase expression than wildtype T-allele (p = 0.026), independent of rs11200638 genotype (p = 0.621). Coherently, vitreous humor HTRA1 expression with rs2672598 CC genotype was significantly higher than that with TT genotype by 2.56 folds (p = 0.02). Furthermore, rs2672598 C-allele was predicted to alter the transcription factor binding sites, but not rs11200638 A-allele. Our results revealed that HTRA1 rs2672598 is more significantly associated with exudative AMD than PCV in ARMS2/HTRA1 region, and it is responsible for elevated HTRA1 transcriptional activity and HTRA1 protein expression.

Common human ANK2 variant confers in vivo arrhythmia phenotypes

BACKGROUND

Human ANK2 (ankyrin-B) loss-of-function variants are directly linked with arrhythmia phenotypes. However, in atypical non-ion channel arrhythmia genes such as ANK2 that lack the same degree of robust structure/function and clinical data, it may be more difficult to assign variant disease risk based simply on variant location, minor allele frequency, and/or predictive structural algorithms. The human ankyrin-B p.L1622I variant found in arrhythmia probands displays significant diversity in minor allele frequency across populations.

OBJECTIVE

The objective of this study was to directly test the in vivo impact of ankyrin-B p.L1622I on cardiac electrical phenotypes and arrhythmia risk using a new animal model.

METHODS

We tested arrhythmia phenotypes in a new "knock-in" animal model harboring the human ankyrin-B p.L1622I variant.

RESULTS

Ankyrin-B p.L1622I displays reduced posttranslational expression in vivo, resulting in reduced cardiac ankyrin-B expression and reduced association with binding-partner Na/Ca exchanger. Ankyrin-B(L1622I/L1622I) mice display changes in heart rate, atrioventricular and intraventricular conduction, and alterations in repolarization. Furthermore, ankyrin-B(L1622I/L1622I) mice display catecholamine-dependent arrhythmias. At the cellular level, ankyrin-B(L1622I/L1622I) myocytes display increased action potential duration and severe arrhythmogenic afterdepolarizations that provide a mechanistic rationale for the arrhythmias.

CONCLUSION

Our findings support in vivo arrhythmogenic phenotypes of an ANK2 variant with unusual frequency in select populations. On the basis of our findings and current clinical data, we support classification of p.L1622I as a "mild" loss-of-function variant that may confer arrhythmia susceptibility in the context of secondary risk factors including environment, medication, and/or additional genetic variation.

Mutational spectrum of Korean patients with corneal dystrophy

Corneal dystrophy typically refers to a group of rare hereditary disorders with a heterogeneous genetic background. A comprehensive molecular genetic analysis was performed to characterize the genetic spectrum of corneal dystrophies in Korean patients. Patients with various corneal dystrophies underwent thorough ophthalmic examination, histopathologic examination, and Sanger sequencing. A total of 120 probands were included, with a mean age of 50 years (SD = 18 years) and 70% were female. A total of 26 mutations in five genes (14 clearly pathogenic and 12 likely pathogenic) were identified in 49 probands (41%). Epithelial-stromal TGFBI dystrophies, macular corneal dystrophy and Schnyder corneal dystrophy (SCD) showed 100% mutation detection rates, while endothelial corneal dystrophies showed lower detection rates of 3%. Twenty six non-duplicate mutations including eight novel mutations were identified and mutations associated with SCD were identified genetically for the first time in this population. This study provides a comprehensive characterization of the genetic aberrations in Korean patients and also highlights the diagnostic value of molecular genetic analysis in corneal dystrophies.

Spectrum of Inherited Metabolic Disorders in Pakistani Children Presenting at a Tertiary Care Centre

OBJECTIVE

To determine the frequency, presentation and outcome of various inherited metabolic diseases in children presenting in a tertiary care hospital, Lahore, Pakistan.

STUDY DESIGN

An observational study.

PLACE AND DURATION OF STUDY

Gastroenterology, Hepatology and Nutrition Department of The Children Hospital and Institute of Child Health, Lahore, from January 2011 to October 2014.

METHODOLOGY

All children aged < 14 years with high suspicion of a metabolic disorder were inducted. Routine and radiological investigation were carried out at the study place. Comprehensive diagnostic testing of particular metabolic disorder was sent abroad. Those with a specific metabolic disorder were included in the study while those with normal metabolic work-up were excluded. All data was collected on preformed proforma.

RESULTS

Atotal of 239 patients were enrolled. Nineteen different types of inherited metabolic disorders were diagnosed in 180 patients; age ranged from 8 days to 14 years. Consanguinity was positive in 175 (97%) among the parents of the affected children, with previously affected siblings in 64 (35.5%). The most frequent disorders were inherited disorders of carbohydrate metabolism (92, 51%), lipid storage disease (59, 32.7%), organic acidemia and energy defects (18, 10%), amino acid disorder (6, 3.3%), and miscellaneous (4, 2.2%). Fifty-eight (32.2%) presented with acute metabolic crisis, 28 (15.5%) patients presented with early onset liver failure, and 24 (13.3%) with mental retardation. Out of these, 16 (8.8%) expired.

CONCLUSION

Glycogen storage disorders being the commonest followed by Gaucher disease and Galactosemia. The associated complications resulted in high morbidity and mortality.

Common genetic variation in ETV6 is associated with colorectal cancer susceptibility

Genome-wide association studies (GWASs) have identified multiple susceptibility loci for colorectal cancer, but much of heritability remains unexplained. To identify additional susceptibility loci for colorectal cancer, here we perform a GWAS in 1,023 cases and 1,306 controls and replicate the findings in seven independent samples from China, comprising 5,317 cases and 6,887 controls. We find a variant at 12p13.2 associated with colorectal cancer risk (rs2238126 in ETV6, P=2.67 × 10(-10)). We replicate this association in an additional 1,046 cases and 1,076 controls of European ancestry (P=0.034). The G allele of rs2238126 confers earlier age at onset of colorectal cancer (P=1.98 × 10(-6)) and reduces the binding affinity of transcriptional enhancer MAX. The mRNA level of ETV6 is significantly lower in colorectal tumours than in paired normal tissues. Our findings highlight the potential importance of genetic variation in ETV6 conferring susceptibility to colorectal cancer.

[Association between IL-27 gene polymorphisms and susceptibility to allergic rhinitis]

Objective: To evaluate the potential association of IL-27 polymorphisms with allergic rhinitis(AR) in a Chinese Han population. Method:A case-control study was performed in 445 Chinese AR patients and 691 healthy controls. Three SNPs in the IL-27p28 gene, including rs153109, rs17855750 and rs181206, were detected using a polymerase chain reaction-restriction fragment length polymorphism assay(PCR-RFLP). Result:A significantly increased prevalence of the rs153109 TT genotype and the T allele was found in AR patients, while a decreased prevalence of the CT and CC genotypes and the C allele was found. For rs153109, the TT genotype and the T allele were significantly associated with the risk of AR, but the CT and CC genotypes and the C allele decreased the risk of AR; for rs17855750, the TT genotype and T allele were risk factors for AR, and the GT genotype and G allele provided protection. TTT and TTC haplotypes in the IL-27 p28 gene were positively correlated with AR, while CGT, CTC and CTT haplotypes were associated with a significantly decreased risk of AR. Conclusion:This study indicates that IL-27 p28 polymorphisms rs153109 and rs17855750 are likely involved in AR susceptibility, making them potentially useful genetic biomarkers for AR susceptibility in the Chinese Han population.

Significant Association of Interleukin-10 Polymorphisms with Childhood Leukemia Susceptibility in Taiwan

Mounting evidence supports the notion that inflammatory processes play a role in carcinogenesis, and interleukin-10 (IL10) is an important inflammatory cytokine. This study aimed to evaluate the contribution of IL10 A-1082G (rs1800896), T-819C (rs3021097) and A-592C (rs1800872) genotypes to the risk of childhood acute lymphoblastic leukemia (ALL) in Taiwan. Associations of these IL10 polymorphic genotypes with ALL risk were analyzed in 266 patients with childhood ALL patients and 266 non-cancer healthy controls by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methodology. The results showed that CC genotype carriers at IL10 T-819C were at lower risk for childhood ALL (odds ratio=0.33, 95% confidence interval=0.16-0.68). On the contrary, AC and CC genotype carriers at IL10 A-592C were at higher risk for childhood ALL (odds ratio=1.73 and 6.34, 95% confidence interval=1.19-2.51 and 3.16-12.72, respectively). There was no difference in the distribution of A-1082G genotypes between childhood ALL and control groups. The genotypes at IL10 T-819C and A-592C may serve as predictive biomarkers for childhood ALL in Taiwan.

A genetic study and meta-analysis of the genetic predisposition of prostate cancer in a Chinese population

Prostate cancer predisposition has been extensively investigated in European populations, but there have been few studies of other ethnic groups. To investigate prostate cancer susceptibility in the under-investigated Chinese population, we performed single-nucleotide polymorphism (SNP) array analysis on a cohort of Chinese cases and controls and then meta-analysis with data from the existing Chinese prostate cancer genome-wide association study (GWAS). Genotyping 211,155 SNPs in 495 cases and 640 controls of Chinese ancestry identified several new suggestive Chinese prostate cancer predisposition loci. However, none of them reached genome-wide significance level either by meta-analysis or replication study. The meta-analysis with the Chinese GWAS data revealed that four 8q24 loci are the main contributors to Chinese prostate cancer risk and the risk alleles from three of them exist at much higher frequencies in Chinese than European populations. We also found that several predisposition loci reported in Western populations have different effect on Chinese men. Therefore, this first extensive single-nucleotide polymorphism study of Chinese prostate cancer in comparison with European population indicates that four loci on 8q24 contribute to a great risk of prostate cancer in a considerable large proportion of Chinese men. Based on those four loci, the top 10% of the population have six- or two-fold prostate cancer risk compared with men of the bottom 10% or median risk respectively, which may facilitate the design of prostate cancer genetic risk screening and prevention in Chinese men. These findings also provide additional insights into the etiology and pathogenesis of prostate cancer.

Loss-of-function Mutation in PMVK Causes Autosomal Dominant Disseminated Superficial Porokeratosis

Disseminated superficial porokeratosis (DSP) is a rare keratinization disorder of the epidermis. It is characterized by keratotic lesions with an atrophic center encircled by a prominent peripheral ridge. We investigated the genetic basis of DSP in two five-generation Chinese families with members diagnosed with DSP. By whole-exome sequencing, we sequencing identified a nonsense variation c.412C > T (p.Arg138*) in the phosphomevalonate kinase gene (PMVK), which encodes a cytoplasmic enzyme catalyzing the conversion of mevalonate 5-phosphate to mevalonate 5-diphosphate in the mevalonate pathway. By co-segregation and haplotype analyses as well as exclusion testing of 500 normal control subjects, we demonstrated that this genetic variant was involved in the development of DSP in both families. We obtained further evidence from studies using HaCaT cells as models that this variant disturbed subcellular localization, expression and solubility of PMVK. We also observed apparent apoptosis in and under the cornoid lamella of PMVK-deficient lesional tissues, with incomplete differentiation of keratinocytes. Our findings suggest that PMVK is a potential novel gene involved in the pathogenesis of DSP and PMVK deficiency or abnormal keratinocyte apoptosis could lead to porokeratosis.

Genetic Association Between Androgen Receptor Gene CAG Repeat Length Polymorphism and Male Infertility: A Meta-Analysis

The association between polymorphism of androgen receptor gene CAG (AR-CAG) and male infertility in several studies was controversial. Based on studies on association between AR-CAG repeat length and male infertility in recent years, an updated meta-analysis is needed. We aimed to evaluate the association between AR-CAG repeat length and male infertility in advantage of the data in all published reports.We searched for reports published before August 2015 using PubMed, CNKI, VIP, and WanFang. Data on sample size, mean, and standard deviation (SD) of AR-CAG repeat length were extracted independently by 3 investigators.Forty-four reports were selected based on criteria. The overall infertile patients and azoospermic patients were found to have longer AR-CAG repeat length (standard mean difference (SMD) = 0.19, 95% confidence interval (CI): 0.10-0.28, P < 0.01; SMD = 0.36, 95% CI: 0.10-0.61, P < 0.01). AR-CAG repeat length was longer in infertile men in Asian, Caucasian, and mixed races (SMD = 0.25, 95% CI: 0.08-0.43, P <0.01; SMD = 0.13, 95% CI: 0.02-0.25, P <0.05; SMD = 0.39, 95% CI: 0.15-0.63, P <0.01). The overall study shows that increased AR-CAG repeat length was associated with male infertility. The subgroup study on races shows that increased AR-CAG repeat length was associated with male infertility in Asian, Caucasian, and mixed races. Increased AR-CAG repeat length was also associated with azoospermia.This meta-analysis supports that increased androgen receptor CAG length is capable of causing male infertility susceptibility.

Stress, relationship satisfaction, and health among African American women: Genetic moderation of effects

We examined whether romantic relationship satisfaction would serve as a link between early and later stressors which in turn would influence the thyroid function index (TFI), an indicator of physiological stress response. Using the framework of genetic susceptibility theory combined with hypotheses derived from the vulnerability-stress-adaptation and stress-generation models, we tested whether the hypothesized mediational model would be conditioned by 5-HTTLPR genotype, with greater effects and stronger evidence of mediation among carriers of the "s" allele. In a sample of African American women in romantic relationships (n = 270), we found that 5-HTTLPR moderated each stage of the hypothesized mediational model in a "for better or for worse" manner. That is genetic polymorphisms function to exacerbate not only the detrimental impact of negative environments (i.e., "for worse effects") but also the beneficial impact of positive environments (i.e., "for better effects"). The effect of early stress on relationship satisfaction was greater among carriers of the "short" allele than among those who did not carry the short allele, and was significantly different in both the "for better" and "for worse" direction. Likewise, the effect of relationship satisfaction on later stressors was moderated in a "for better "or "for worse" manner. Finally, impact on physiological stress, indexed using TFI level, indicated that the impact of later stressors on TFI level was greater in the presence of the short allele, and also followed a "for better" or "for worse" pattern. As expected, the proposed mediational model provided a better fit for "s" allele carriers.

Correlation between polymorphisms of BRAF gene and papillary thyroid carcinoma

BACKGROUND

Papillary thyroid carcinoma (PTC), which accounts for 80% of all thyroid cancers, has an increasing incidence over these years. Single nucleotide polymorphisms (SNPs) of BRAF were considered to be one of well-established risk factors leading to development of PTC. The aim of this study was to investigate whether the common mutations of BRAF could elevate significantly the risk of PTC in a Chinese population.

METHODS

Four SNPs (rs11762469, rs17623204, rs1267636 and rs3748093) of BRAF were selected through our filter by Haploview 4.2 software with HapMap databases. We used the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to genotype the four SNPs in blood samples of 618 subjects (206 patients with PTC and 412 healthy controls). The correlation between BRAF polymorphisms and PTC risk was assessed using student t-test and chi-square test.

RESULTS

The results showed that mutation in rs3748093 was significantly associated with an increased risk of PTC in allele model (A allele vs. T allele, OR = 1·68, 95% CI = 1·16-2·43, P = 0·006), dominant model (TA + AA vs TT, OR = 1·64, 95% CI = 1·08-2·48, P = 0·019) and homozygote model (AA vs. TT, OR = 2·94, 95% CI = 1·00-8·61, P = 0·040). However, the other three SNPs (rs11762469, rs17623204 and rs1267636) were shown to have no association with the risk of PTC.

CONCLUSIONS

Our results indicated that polymorphism of rs3748093*A was significantly correlated with an increased risk of PTC in a Chinese population. Further investigation on the aetiological mechanism of PTC is needed to validate our results.

A Genome Wide Study of Copy Number Variation Associated with Nasopharyngeal Carcinoma in Malaysian Chinese Identifies CNVs at 11q14.3 and 6p21.3 as Candidate Loci

Background

Nasopharyngeal carcinoma (NPC) is a neoplasm of the epithelial lining of the nasopharynx. Despite various reports linking genomic variants to NPC predisposition, very few reports were done on copy number variations (CNV). CNV is an inherent structural variation that has been found to be involved in cancer predisposition.

Methods

A discovery cohort of Malaysian Chinese descent (NPC patients, n = 140; Healthy controls, n = 256) were genotyped using Illumina^® HumanOmniExpress BeadChip. PennCNV and cnvPartition calling algorithms were applied for CNV calling. Taqman CNV assays and digital PCR were used to validate CNV calls and replicate candidate copy number variant region (CNVR) associations in a follow-up Malaysian Chinese (NPC cases, n = 465; and Healthy controls, n = 677) and Malay cohort (NPC cases, n = 114; Healthy controls, n = 124).

Results

Six putative CNVRs overlapping GRM5, MICA/HCP5/HCG26, LILRB3/LILRA6, DPY19L2, RNase3/RNase2 and GOLPH3 genes were jointly identified by PennCNV and cnvPartition. CNVs overlapping GRM5 and MICA/HCP5/HCG26 were subjected to further validation by Taqman CNV assays and digital PCR. Combined analysis in Malaysian Chinese cohort revealed a strong association at CNVR on chromosome 11q14.3 (P_combined = 1.54x10^-5; odds ratio (OR) = 7.27; 95% CI = 2.96–17.88) overlapping GRM5 and a suggestive association at CNVR on chromosome 6p21.3 (P_combined = 1.29x10^-3; OR = 4.21; 95% CI = 1.75–10.11) overlapping MICA/HCP5/HCG26 genes.

Conclusion

Our results demonstrated the association of CNVs towards NPC susceptibility, implicating a possible role of CNVs in NPC development.

Associations between two single-nucleotide polymorphisms (rs1801278 and rs2943641) of insulin receptor substrate 1 gene and type 2 diabetes susceptibility: a meta-analysis

The objective of the study is to assess the association between rs1801278 and rs2943641 of insulin receptor substrate 1 gene (IRS1) and the susceptibility to type 2 diabetes. A literature search strategy was conducted to identify all references lists of relevant studies. The fixed or random effect model was used to calculate the pooled ORs on the basis of heterogeneity. Further analyses were performed to explore the sources of heterogeneity by sensitivity analysis, meta-regression analysis, and subgroup analysis. There was significant association between rs1801278 and type 2 diabetes risk in recessive model (AA vs. GA + GG, p = 0.043) and codominant model (AA vs. GG, p = 0.007). Subgroup analysis showed that the association between rs1801278 and type 2 diabetes risk was significant in dominant model (GA + AA vs. GG, p = 0.044), codominant model (GA vs. GG, p = 0.039), codominant model (AA vs. GG, p = 0.044), overdominant model (GG + AA vs. GA, p = 0.037) in Asian and codominant model (AA vs. GG, p = 0.039) in Caucasian of rs1801278. The association between rs2943641 and type 2 diabetes risk was significant in codominant model (CT vs. CC, p = 0.023) in Caucasian. This meta-analysis suggests that rs1801278 may play a role in type 2 diabetes risk, especially in Asian. It also indicates that rs2943641 may be associated with type 2 diabetes risk in Caucasian. Further larger studies should be performed to warrant confirmation.

Variants and haplotypes in Flap endonuclease 1 and risk of gallbladder cancer and gallstones: a population-based study in China

The role of FEN1 genetic variants on gallstone and gallbladder cancer susceptibility is unknown. FEN1 SNPs were genotyped using the polymerase chain reaction-restriction fragment length polymorphism method in blood samples from 341 gallbladder cancer patients and 339 healthy controls. The distribution of FEN1-69G > A genotypes among controls (AA, 20.6%; GA, 47.2% and GG 32.2%) was significantly different from that among gallbladder cancer cases (AA, 11.1%; GA, 48.1% and GG, 40.8%), significantly increased association with gallbladder cancer was observed for subjects with both the FEN1-69G > A GA (OR = 1.73, 95% CI = 1.01-2.63) and the FEN1-69G > A GG (OR = 2.29, 95% CI = 1.31-3.9). The distribution of FEN1 -4150T genotypes among controls (TT, 21.8%;GT, 49.3% and GG 28.9%) was significantly different from that among gallbladder cancer cases (TT, 12.9%; GT, 48.4% and GG 38.7%), significantly increased association with gallbladder cancer was observed for subjects with both the FEN1-4150T GT(OR = 1.93, 95% CI = 1.04-2.91) and the FEN1-4150T GG(OR = 2.56, 95% CI = 1.37-5.39). A significant trend towards increased association with gallbladder cancer was observed with potentially higher-risk FEN1-69G > A genotypes (P < 0.001, χ2 trend test) and FEN14150G > T (P < 0.001, χ2 trend test) in gallstone presence but not in gallstone absence (P = 0.81, P = 0.89, respectively). In conclusion, this study revealed firstly that FEN1 polymorphisms and haplotypes are associated with gallbladder cancer risk.

Genome-wide association study identifies two new susceptibility loci for colorectal cancer at 5q23.3 and 17q12 in Han Chinese

Genome-wide association studies (GWAS) have reported a number of loci harboring common variants that influence risk of colorectal cancer (CRC) in European descent. But all the SNPs identified explained a small fraction of total heritability. To identify more genetic factors that modify the risk of CRC, especially Chinese Han specific, we conducted a three-stage GWAS including a screening stage (932 CRC cases and 966 controls) and two independent validations (Stage 2: 1,759 CRC cases and 1,875 controls; Stage 3: 943 CRC cases and 1,838 controls). In the combined analyses, we discovered two novel loci associated with CRC: rs12522693 at 5q23.3 (CDC42SE2-CHSY3, OR = 1.31, P = 2.08 × 10-8) and rs17836917 at 17q12 (ASIC2-CCL2, OR = 0.75, P = 4.55 × 10-8). Additionally, we confirmed two previously reported risk loci, rs6983267 at 8q24.21 (OR = 1.17, P = 7.17 × 10-7) and rs10795668 at 10p14 (OR = 0.86, P = 2.96 × 10-6) in our cohorts. These results bring further insights into the CRC susceptibility and advance our understanding on etiology of CRC.

GABRB2 Haplotype Association with Heroin Dependence in Chinese Population

Substance dependence is a frequently observed comorbid disorder in schizophrenia, but little is known about genetic factors possibly shared between the two psychotic disorders. GABRB2, a schizophrenia candidate gene coding for GABAA receptor β2 subunit, is examined for possible association with heroin dependence in Han Chinese population. Four single nucleotide polymorphisms (SNPs) in GABRB2, namely rs6556547 (S1), rs1816071 (S3), rs18016072 (S5), and rs187269 (S29), previously associated with schizophrenia, were examined for their association with heroin dependence. Two additional SNPs, rs10051667 (S31) and rs967771 (S32), previously associated with alcohol dependence and bipolar disorder respectively, were also analyzed. The six SNPs were genotyped by direct sequencing of PCR amplicons of target regions for 564 heroin dependent individuals and 498 controls of Han Chinese origin. Interestingly, it was found that recombination between the haplotypes of all-derived-allele (H1; OR = 1.00) and all-ancestral-allele (H2; OR = 0.74) at S5-S29 junction generated two recombinants H3 (OR = 8.51) and H4 (OR = 5.58), both conferring high susceptibility to heroin dependence. Additional recombination between H2 and H3 haplotypes at S1-S3 junction resulted in a risk-conferring haplotype H5 (OR = 1.94x109). In contrast, recombination between H1 and H2 haplotypes at S3-S5 junction rescued the risk-conferring effect of recombination at S5-S29 junction, giving rise to the protective haplotype H6 (OR = 0.68). Risk-conferring effects of S1-S3 and S5-S29 crossovers and protective effects of S3-S5 crossover were seen in both pure heroin dependent and multiple substance dependence subgroups. In conclusion, significant association was found with haplotypes of the S1-S29 segment in GABRB2 for heroin dependence in Han Chinese population. Local recombination was an important determining factor for switching haplotypes between risk-conferring and protective statuses. The present study provide evidence for the schizophrenia candidate gene GABRB2 to play a role in heroin dependence, but replication of these findings is required.

Dependable and Efficient Clinical Molecular Diagnosis of Chinese RP Patient with Targeted Exon Sequencing

Retinitis pigmentosa (RP) is the most common inherited retinal disease. It is a clinically and genetically heterogeneous disorder, which is why it is particularly challenging to diagnose. The aim of this study was to establish a targeted next-generation sequencing (NGS) approach for the comprehensive, rapid, and cost-effective clinical molecular diagnosis of RP. A specific hereditary eye disease enrichment panel (HEDEP) based on exome capture technology was used to collect the protein coding regions of 371 targeted hereditary eye disease genes, followed by high-throughput sequencing on the Illumina HiSeq2000 platform. From a cohort of 34 Chinese RP families, 13 families were successfully diagnosed; thus, the method achieves a diagnostic rate of approximately 40%. Of 16 pathogenic mutations identified, 11 were novel. Our study demonstrates that targeted capture sequencing offers a rapid and effective method for the molecular diagnosis of RP, which helps to provide a more accurate clinical diagnosis and paves the way for genetic counseling, family planning, and future gene-targeted treatment.

The Impact of PNPLA3 rs738409 Genetic Polymorphism and Weight Gain ≥10 kg after Age 20 on Non-Alcoholic Fatty Liver Disease in Non-Obese Japanese Individuals

Non-alcoholic fatty liver disease (NAFLD) in non-obese individuals is inadequately elucidated. We aim to investigate the impact of known genetic polymorphisms on NAFLD and the interaction between genetic risks and weight gain on NAFLD in obese and non-obese Japanese individuals. A total of 1164 participants who received health checkups were included. Participants with excessive alcohol consumption, with viral hepatitis or other inappropriate cases were excluded. Fatty liver was diagnosed by ultrasonography. Participants with a body mass index (BMI) of <18.5 kg/m2, 18.5-22.9 kg/m2, 23.0-24.9 kg/m2 and ≥25 kg/m2 were classified underweight, normal weight, overweight and obese, respectively. Self-administered questionnaire for lifestyle was assessed and a total of 8 previously reported genetic polymorphisms were chosen and examined. In all, 824 subjects were enrolled. The overall prevalence of NAFLD was 33.0%: 0% in underweight, 15.3% in normal weight, 41.1% in overweight and 71.7% in obese individuals. The prevalence of NAFLD is more affected by the G allele of patatin-like phospholipase domain-containing protein 3 (PNPLA3) rs738409 in normal weight (odds ratio (OR) 3.52; 95%-CI: 1.42-8.71; P = 0.0063) and in overweight individuals (OR 2.60; 95%-CI: 1.14-5.91; P = 0.0225) than in obese individuals (not significant). Moreover, the G allele of PNPLA3 rs738409 and weight gain ≥10 kg after age 20 had a joint effect on the risk of NAFLD in the normal weight (OR 12.00; 95% CI: 3.71-38.79; P = 3.3×10-5) and the overweight individuals (OR 13.40; 95% CI: 2.92-61.36; P = 0.0008). The G allele of PNPLA3 rs738409 is a prominent risk factor for NAFLD and the interaction between the PNPLA3 rs738409 and weight gain ≥10 kg after age 20 plays a crucial role in the pathogenesis of NAFLD, especially in non-obese Japanese individuals.

Single nucleotide polymorphism rs11669203 in TGFBR3L is associated with the risk of neuroblastoma in a Chinese population

With a primary mortality, neuroblastoma (NB) is the most common extracranial solid tumor in childhood. Amplification of the MYCN (v-myc avian myelocytomatosis viral oncogene neuroblastoma derived homolog) oncogene is observed in 20-30 % of NB cases, a feature which also characterizes a highly aggressive subtype of the disease. However, the systematic study of association between single nucleotide polymorphisms (SNPs) in MYCN-regulated genes and the risk of NB has not been investigated. In the current study, we scanned a set of 16 SNPs located within known or predicted MYCN binding sites in a cohort of 247 patients of Chinese origin with neuroblastic family tumors, including neuroblastoma (NB), ganglioneuroma (GN), and ganglioneuroblastoma (GNB), and in 290 cancer-free controls to determine whether any of the tested SNPs are associated with neuroblastic family tumors. We found that the rs11669203 G>C polymorphism, located in TGFBR3L promoter, is significantly associated with the risk of NB. Further, we found that this association is site specific to adrenal NB compared to non-adrenal NB. In addition, transcriptome analysis indicated that increased expression of TGFBR3L is strongly correlated with poor survival. The SNP rs11669203 located at the MYCN binding site of TGFBR3L is significantly associated with elevated risk of NB, and abnormal MYCN-regulated TGFBR3L expression may contribute to NB oncogenesis.

Interaction between common breast cancer susceptibility variants, genetic ancestry, and nongenetic risk factors in Hispanic women

BACKGROUND

Most genetic variants associated with breast cancer risk have been discovered in women of European ancestry, and only a few genome-wide association studies (GWAS) have been conducted in minority groups. This research disparity persists in post-GWAS gene-environment interaction analyses. We tested the interaction between hormonal and lifestyle risk factors for breast cancer, and ten GWAS-identified SNPs among 2,107 Hispanic women with breast cancer and 2,587 unaffected controls, to gain insight into a previously reported gene by ancestry interaction in this population.

METHODS

We estimated genetic ancestry with a set of 104 ancestry-informative markers selected to discriminate between Indigenous American and European ancestry. We used logistic regression models to evaluate main effects and interactions.

RESULTS

We found that the rs13387042-2q35(G/A) SNP was associated with breast cancer risk only among postmenopausal women who never used hormone therapy [per A allele OR: 0.94 (95% confidence intervals, 0.74-1.20), 1.20 (0.94-1.53), and 1.49 (1.28-1.75) for current, former, and never hormone therapy users, respectively, Pinteraction 0.002] and premenopausal women who breastfed >12 months [OR: 1.01 (0.72-1.42), 1.19 (0.98-1.45), and 1.69 (1.26-2.26) for never, <12 months, and >12 months breastfeeding, respectively, Pinteraction 0.014].

CONCLUSIONS

The correlation between genetic ancestry, hormone replacement therapy use, and breastfeeding behavior partially explained a previously reported interaction between a breast cancer risk variant and genetic ancestry in Hispanic women.

IMPACT

These results highlight the importance of understanding the interplay between genetic ancestry, genetics, and nongenetic risk factors and their contribution to breast cancer risk.

[Genome-wide association in type 2 diabetes and its clinical application]

Diabetes mellitus is a complex and chronical disease, which represents one of the biggest health issues the world, with alarming numbers and constantly increasing it demands the creation of new diagnostic, therapeutic and preventive techniques. The complete Genome Wide Association (GWA) in type 2 diabetes (T2D) is a useful research tool for the characterization of genetic markers and physiopathogenic pathways, with potential clinical utility either as a T2D risk prediction or its complications. In Mexico is necessary to make a comprehensive dissection of the genetic background of T2D by the complex genetic mosaic of our population and increase the knowledge of the molecular and pathophysiological mechanisms that lead to this condition. There are several genetic studies for the Mexican population, linked to the 1000 genomes project, which have led to define some specific genetic markers for our population which are not described in European populations, until the moment, 78 loci have been associated with T2D. Recently in the global meta-analysis, with the participation of Mexico, we demonstrated at least 7 new variants associated with T2D.

Association of ABCB1 and FLT3 Polymorphisms with Toxicities and Survival in Asian Patients Receiving Sunitinib for Renal Cell Carcinoma

Sunitinib is a tyrosine kinase inhibitor used as first-line treatment for metastatic renal cell carcinoma (mRCC). Asian ethnicity has been previously associated with lower clearance and greater toxicities for sunitinib treatment, relative to Caucasian ethnicity. Research focusing on identifying corresponding biomarkers of efficacy and toxicity has been hitherto conducted in Caucasian populations, and few of the reported associations have been externally validated. Our work thus aims to investigate candidate biomarkers in Asian patients receiving sunitinib, comparing the observed genotype effects with those reported in Caucasian populations. Using data from 97 Asian mRCC patients treated with sunitinib, we correlated 7 polymorphisms in FLT3, ABCB1, VEGFR2, ABCG2 and BIM with patient toxicities, response, and survival. We observed a stronger association of FLT3 738T genotype with leucopenia in our Asian dataset than that previously reported in Caucasian mRCC patients (odds ratio [OR]=8.0; P=0.03). We observed significant associations of FLT3 738T (OR=2.7), ABCB1 1236T (OR=0.3), ABCB1 3435T (OR=0.1), ABCB1 2677T (OR=0.4), ABCG2 421A (OR=0.3) alleles and ABCB1 3435, 1236, 2677 TTT haplotype (OR=0.1) on neutropenia. Primary resistance (OR=0.1, P=0.004) and inferior survival (progression-free: hazard ratio [HR]=5.5, P=0.001; overall: HR=5.0, P=0.005) were associated with the ABCB1 3435, 1236, 2677 TTT haplotype. In conclusion, ABCB1 and FLT3 polymorphisms may be helpful in predicting sunitinib toxicities, response and survival benefit in Asian mRCC patients. We have also validated the association between FLT3 738T and sunitinib-induced leucopenia previously reported in Caucasian populations, but have not validated other reported genetic associations.