Objective To investigate the distribution of single nucleotide polymorphisms (SNPs)in CAPN10 gene in Chinese population and their relation with type 2 diabetes mellitus inHan people of Northern China. Methods CAPN10 gene was sequenced to detect SNPs indifferent nationalities of China. Five SNPs were chosen to perform case-control study andhaplotype analysis in 156 normal Han people of Northern China and 173 type 2 diabetes. OneSNP was also analyzed with transmission-disequilibrium test (TDT) and sib transmission-disequilibrium test (STDT) in 68 type 2 diabetes pedigrees (377 people). Results A totalof 40 SNPs were identified in length of 8 936bp, with an average of 1 in every 223bp. TheSNPs in CAPN10 gene did not distribute evenly and the SNPs in Chinese were different fromthose reported in Mexican American. There was no significantly statistical difference in theallele frequency of the 5 SNPs between case and control, and the haplotype frequencies inthe two groups were not significantly different. No positive results was found in TDT andSTDT analysis. Conclusions The SNP distribution of CAPN10 gene differs in differentnationalities. The studied SNPs in CAPN10 gene may not be the major susceptibility onesof type 2 diabetes mellitus in Han people of Northern China. Objective To investigate the distribution of single nucleotide polymorphisms (SNPs) in CAPN10 gene in Chinese population and their relation with type 2 diabetes mellitus in Han people of Northern China. Methods CAPN10 gene was sequenced to detect SNPs indifferent nationalities of China. Five SNPs were chosen to perform case-control study and haplotype analysis in 156 normal Han people of Northern China and 173 type 2 diabetes. One SNP was also analyzed with transmission-disequilibrium test (TDT) and sib transmission-disequilibrium test (STDT) in 68 type 2 diabetes pedigrees There was no distribution evenly and the SNPs in Chinese were different fromthose reported in Mexican American. There was no significant difference in the length of 8 936 bp, with an average of 1 in every 223 bp. Statistical difference in theallele frequency of the 5 SNPs between case and control, and the haplotype frequencies inthe two groups were not s ignificantly different. No positive results was found in TDT and STDT analysis. Conclusions The SNP distribution of CAPN10 gene differs in different nationalities. The study SNPs in CAPN10 gene may not be the major susceptibility ones of type 2 diabetes mellitus in Han people of Northern China.