CRYAB-650 C>G (rs2234702) affects susceptibility to Type 1 diabetes and IAA-positivity in Swedish population.

BACKGROUND: Single nucleotide polymorphisms (SNPs) in the promoter region of CRYAB gene have been associated with in multiple sclerosis. CRYAB gene, which encodes alpha B-crystallin (a member of small heat shock protein), was reported as a potential autoimmune target. In this study we investigated whether SNPs in the promoter region of CRYAB gene were also important in the etiology of Type 1 diabetes (T1D). METHODS: Genotyping of SNPs in the promoter region of CRYAB gene was performed in a Swedish cohort containing 444 T1D patients and 350 healthy controls. Three SNPs were included in this study: CRYAB-652 A>G (rs762550), -650 C>G (rs2234702) and -249 C > G (rs14133). Two SNPs (CRYAB-652 and -650) were not included in previous genome wide association studies. RESULTS: CRYAB-650 (rs2234702)*C allele was significantly more frequent in patients than in controls (OR = 1.48, Pc = 0.03). CRYAB-650*C allele was associated with IAA positivity (OR = 8.17, Pc < 0.0001) and IA-2A positivity (OR = 2.14, Pc = 0.005) in T1D patients. This association with IAA was amplified by high-risk HLA carrier state (OR = 10.6, P < 0.0001). No association was found between CRYAB-650 and other autoantibody positivity (GADA and ICA). CRYAB haplotypes were also associated with IAA and IA-2A positivity (highest OR = 2.07 and 2.11, respectively), these associations remain in high HLA-risk T1D patients. CONCLUSIONS: CRYAB-650 was associated with T1D in the Swedish cohort we studied. CRYAB-650*C allele might confers susceptibility to the development of T1D. CRYAB-650 was also associated with the development of IAA-positivity in T1D patients, especially in those carrying T1D high-risk HLA haplotypes.

Association of lipoprotein lipase Hind III and Ser 447 Ter polymorphisms with dyslipidemia in Asian Indians.

Studies have shown an association between the lipoprotein lipase gene and dyslipidemia and atherosclerosis in some populations. The aim of this study was to investigate the association between the common lipoprotein lipase HindIII (T-G) and Ser447Ter (C-G) polymorphisms with dyslipidemia in Asian Indians, who are known to have very high rates of premature coronary artery disease. A total of 1,015 subjects, comprising 550 normal glucose-tolerant subjects and 465 patients with type 2 diabetes, were randomly selected from the Chennai Urban Rural Epidemiology Study. The total serum cholesterol, high-density lipoprotein (HDL) cholesterol, and serum triglyceride levels were assayed using enzymatic methods. Low-density lipoprotein cholesterol was calculated using the Friedewald formula. Genotyping was done using the polymerase chain reaction-restriction fragment length polymorphism method. A significant association was found between the H+ allele of HindIII with low HDL cholesterol and elevated triglyceride levels. The Ser allele of Ser447Ter was also strongly associated with low HDL cholesterol levels. No association was found between the H+ allele and Ser Allele with the total or low-density lipoprotein cholesterol levels. Group-wise haplotype frequencies were generated using the expectation-maximization algorithm to detect differences in overall haplotype frequency profiles between the case-control groups. The haplotype analysis showed that the H+ Ser and H- Ter were the "high-risk" and "low-risk" haplotypes for low HDL cholesterol and elevated triglyceride levels, respectively. In conclusion, the H+ Ser haplotype of the lipoprotein lipase gene was associated with low HDL cholesterol levels and hypertriglyceridemia in Asian Indians.