Screen Of Susceptibility Gene CDC2L2 Of T2D In Chinese And Function Analysis Of The Gene, Involving In Apoptosis Of The Paneritic β-Cell

Background and Objective Type 2 diabetes is a complex disorder with a strong genetic background.Our previous genome-wide scanning suggested that 3 regions in chromosomes 1 showed evidence of linkage with type 2 diabetes.Aim of this paper is to search for the susceptibility variant(s) of type 2 diabetes in these three susceptible regions by genotyping SNP markers in case-control DNA samples.Another purpose of this study is to gain insight into the function of these genes.Methods SNPs from 4 candidate genes(sAC,PANK4,CASPASE9 and CDC2L2) in the mapped regions were chosen from public SNP data or identified by sequencing the samples.These loci are further evaluated in Han Chinese individuals comprising of 467 patients and 569 normal subjects and 76 parent-offspring trios by TDT analysis.The haplotypes within a gene are further analyzed.We construct of expression vector of p58 PITSLRE and p110C and transfect beta-cell(INS-1).Using of western blotting to measure the expression and phosphorylation levels of the key molecules in the pathway relating to cell survival and apoptosis.Results SNPs of PANK4,CASPASE9 and sAC genes didn't show significant association with diabetes status.Six SNPs of CDC2L2 gene were shown to be significantly associated with T2D:rs1059831:P = 0.043,OR = 0.81(CI 95% 0.66-0.99);SNP33:P= 0.028,OR = 0.79(CI 95%0.65-0.98);SNP11:P= 0.018, OR = 0.78(CI 95%0.64-0.96);SNP36:P= 0.040,OR = 0.81(CI 95%0.66-0.99); rs11488590:P= 0.035,OR = 0.80(CI 95%0.66-0.98) and SNP30:P= 0.029,OR = 0.80(CI 95%0.66-0.98).The pairs of these six SNPs in CDC2L2 gene showed strong LD(r~2＞0.5,P＜0.001).Two haplotypes in CDC2L2 were observed to be associated with T2D(T-A-G-G-C-A:P=0.041,OR=1.22(CI 95%1.01-1.47) and C- -A-A-T-G:P=0.015,OR=0.77(CI 95%0.63 - 0.95)).The data informatively showed that offspring carrying the protective alleles in these six variations had a lower risk for T2D under dominant model(rs1059831:P=0.026;SNP33: P=0.0097;SNP11:P=0.025;SNP36:P=0.042;rs11488590:P=0.026).When individuals were stratified by age,sex and Body Mass Index,the SNP11 of CDC2L2 gene was strongly associated with T2D female patients,those who were over 44 years old,whose BMI was less than 23(P = 0.018,0.011 and 0.0089, respectively).However,it was not replicated in family-based TDT analysis(P = 0.085,OR = 0.63(CI 95%0.34 - 1.06)).In spite of this,the TDT results also clearly indicated that minor-allele for SNP11 was a protective allele for T2D, supporting the result performed in case-control study.In addition,rs7535528 of PANK4 is strongly associated with T2D female patients and those who BMI was less than 23(P = 0.033 and 0.020,respectively).The data showed that the synergetic effect of PANK4 and CDC2L2 is responsible for the development of type 2 diabetes.Overexpression of p58 and p110C in INS-1 cell both can decrease the activity of FAK,but the means of them were different:p58 was by decreasing phosphorylation level of FAK(Tyr 397) and p110C was by decreasing the level of FAK expression.Conclusion Our data confer that the CDC2L2 gene may contribute to the susceptibility of type 2 diabetes in Northern Han Chinese population.P58 PITSLRE and p110C might be involved in apoptosis by regulating the intergrin-FAK pathway.