The hormone ghrelin has an important role in a wide range of metabolic and nonmetabolic processes. Ghrelin gene polymorphisms have been reported to influence obesity or lipid abnormalities in some ethnic groups. This study was conducted mainly to examine the possible association of ghrelin - 604G > A and Leu72Met polymorphisms with obesity and related traits in a Southwest Chinese population. Three hundred and eighty-six Han Chinese individuals (118 obese and 268 normal weight control subjects) in the Chengdu area were studied using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Clinical and biochemical parameters were also analyzed. The genotype and allele frequencies of ghrelin gene polymorphisms in participants with obesity showed no significant difference compared to those in nonobese controls. However, in the nonobese control group, carriers of genotype Met/Met at the Leu72Met site had higher serum TC and LDL-C concentrations than those of the Leu/Leu genotype (P < 0.05). When nonobese subjects were stratified by sex, the genotype-dependent effects on TC and LDL-C were more evident, although this was observed only in females. In addition, genotype-related effects on these lipid parameters at this site were observed in male obese subjects only. The Leu72Met polymorphism of the ghrelin gene is associated with altered plasma TC and LDL-C concentrations, and the effects on TC and LDL-C levels are sex-dependent in both nonobese and obese subjects in the Chinese population of the Chengdu area.
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