Gly15Gly polymorphism within the human adipocyte-specific apM-1gene but not Tyr111His polymorphism is associated with higher levels of cholesterol and LDL-cholesterol in caucasian patients with type 2 diabetes

The recently described mutations within the human adipocyte-specific apM-1 gene might play a: role in the, pathogenesis of obesity, type 2 diabetes an d related metabolic disorders. Design: Frequency of apM-1 gene polymorphism s and their association with metabolic parameters was evaluated in a popula tion-based sample of 556 type 2 (316 males / 240 females) diabetic patients . PCR-based RFLP analysis was performed in blood samples. The T --> G trans ition at nucleotide +45 within exon-2 [GIy15Gly] was detected with an allel ic frequency of 0.91 for the wildtype allele and 0.09 for the mutated allel e. The missense point mutation (TAC --> CAC) at nucleotide +331 within exon 3 [Tyr111-His] was detected with an allelic frequency of 0.97 and 0.03, re spectively. These frequencies did not differ from a non-diabetic cohort exa mined earlier. Concerning the Gly15Gly polymorphism, the Tr-genotype was fo und in 457 (82.2%) and the TG-genotype in 99 (17.8%), concerning the Tyr111 His polymorphism, TT-genotype was found in 525 (94.4) and TC-genotype in 31 (5.6%) of type 2 diabetic patients. In TG-genotype as compared to T-F-geno type significantly more patients had LDL-serum levels in high LDL-classes ( < 150 mg/dl: 24.4% (TG) vs. 41.4%. (TT), 150mg/dl to 190mg/dl: 40.0% (TG) v s. 33.9% (TT), > 190 mg/l: 35.6% (TIG) vs. 25.0% (Tr); p=0.010). No differe nces in serum levels of lipids were found in genotype-subgroups of the Tyr1 11His polymorphism. Thus, Gly15Gly polymorphism of apM-1 gene might play a role in dyslipidaemia in type 2 diabetic patients.