Detection of an amino acid polymorphism in hormone-sensitive lipase in Japanese subjects

Hormone-sensitive lipase (HSL) plays an important role in energy metabolism by controlling the hydrolysis of triglycerides stored in adipose tissue. To investigate whether mutations in the HSL gene are associated with non-insulin-dependent diabetes mellitus (NIDDM), we screened for mutations of this gene using single-stranded conformation polymorphism (SSCP) in 35 Japanese subjects with NIDDM. SSCP analysis identified a variant pattern in axon 4, and the sequence showed that this variant pattern resulted from amino acid polymorphism (Arg309Cys). Subsequent study showed that this polymorphism was found in 18 of 151 NIDDM patients and 10 of 97 nondiabetic subjects, but allele frequency was not significantly different between the two groups (P = .7). Body mass index, serum triglyceride, and high-density lipoprotein (HDL) cholesterol were not different in subjects with and without the polymorphism. But serum total cholesterol was higher in subjects with the polymorphism than in subjects without it (P = .0005). These data indicate that this HSL polymorphism is not associated with NIDDM, obesity, and serum triglyceride level. However, an effect of the polymorphism to elevate serum total cholesterol has not been excluded, although further study is necessary to resolve its association with cholesterol metabolism.