Investigating the rs2237892 and rs231362 Polymorphisms of KCNQ1 Gene Associations with Type 2 Diabetes in an Iranian Population (Yazd Province)

Objective: Type 2 diabetes (T2DM) is a worldwide prevalent metabolic disorder and the cause of many morbidities and mortalities. KCNQ1 gene encodes α-subunit of voltage-gated potassium (K+) channel which plays a role in insulin secretion in the pancreas, thus its variants may confer susceptibility to diabetes. Recognition of genetic variants involved in T2DM could help the early diagnosis and prevention of the disease. The main purpose of this paper was to investigate the frequencies of rs231362 and rs2237892 polymorphisms of KCNQ1 gene in T2DM patients and comparing these frequencies with normal subjects in an Iranian population from Yazd province, Iran. Materials and Methods: This case-control study was conducted on 166 patients with T2DM and 168 normal subjects. After obtaining the informed consent, 5 ml peripheral blood was taken from the cases and controls and then DNA was extracted. The molecular investigation was done using 4-primer ARMS PCR and PCR-RFLP methods. Results: Statistical analysis showed that GG genotype [OR= 3.9 (2.1-7.1), P-value< 0.001] and G allele [OR=2.85 (2.07-3.93), P-value< 0.001] frequency of rs231362 polymorphism was significantly different between case and control groups. While rs2237892 polymorphism did not show any differences between the two groups. Conclusion: The result of this study showed that GG genotype and G allele of rs231362 polymorphism can be related to T2DM susceptibility in the population under study.

Association of polymorphisms of the KCNQ1 and ADIPOQ genes with the prognosis of type 2 diabetes

Цель работы - изучение ассоциации однонуклеотидных полиморфизмов rs2237892 гена KCNQ1 и rs6773957 гена ADIPOQ с сахарным диабетом 2 типа (СД2). На основе проспективного обследования репрезентативной популяционной выборки жителей г.Новосибирска сформированы две группы по принципу «случай - контроль». Группа СД2 (n=443, средний возраст 56,2 лет, мужчины - 28,8%, женщины - 71,2%), группа контроля (n=532, средний возраст 56,1 лет, мужчины - 33,8%, женщины - 66,2%) сформированы из банка ДНК международного исследования HAPIEE. ДНК выделена методом фенолхлороформной экстракции. Генотипирование выполнено методом ПЦР с последующим анализом полиморфизма длин рестрикционных фрагментов. Статистическая обработка проведена с использованием программного пакета SPSS 16.0. По частотам генотипов и аллелей полиморфизмов rs2237892 гена KCNQ1 и rs6773957 гена ADIPOQ не выявлено статистически значимых различий между группами, в том числе и при разделении по полу и возрасту (p>0,05). Значимого влияния rs2237892 гена KCNQ1 и rs6773957 гена ADIPOQ на риск развития СД2 не обнаружено. The aim of this work is study the association of rs2237892 and rs6773957 with T2D in a case-control study. Two groups was formed based on the case - control study. The T2D group is 443 person (mean age 56.2 years, men - 28.8 %, women - 66.2 %), the control group was selected according to the sex and age from the DNA bank of project Health, Alcohol and Psychosocial factors In Eastern Europe (HAPIEE) (n = 532, mean age 56.1 years, men - 33.8 %, women - 66.2 %). DNA was isolated by phenol-chloroform extraction. Genotyping was done by PCR followed by analysis of restriction fragment length polymorphism. Statistical processing was performed using the SPSS 16.0 software package. The genotypes frequencies of rs2237892 of the KCNQ1 gene and rs6773957 of the ADIPOQ gene did not show statistically significant differences. There was no significant effect of rs2237892 of the KCNQ1 gene and rs6773957 of the ADIPOQ gene on the risk of developing type 2 diabetes.

Relationship between KCNQ1 gene polymorphisms and type 2 diabetes in the population of northwestern China and a meta-Analysis

Aims The purpose of this study was to explore the correlation between Potassium Voltage-Gated Channel Subfamily Q Member 1 (KCNQ1) gene polymorphisms and the risk of type 2 diabetes mellitus (T2DM) and its clinical indicators in the population of northwestern China, and conducted a meta-analysis on two polymorphic loci that have been studied frequently and controversial. Methods A case control study was conducted, involving 508 patients and 503 healthy individuals in the population of northwest China, and evaluated the associations using the χ2 test, Fisher's exact test, T test, and genetic model analyses. Results We discovered that rs2237895 rs2283228, rs163184, and rs163177 were associated with susceptibility to T2DM. Rs231362 rs231356, rs8181588 were related to the risk of T2DM after stratification. The results of meta-analysis also confirmed that rs2237895 and rs2283228 were strongly correlated with T2DM risk, especially in the East Asian population. Conclusions This study provides evidence for the correlation between KCNQ1 gene polymorphisms and T2DM in the population of northwestern China.