Ghrelin gene variants and eating disorders.

Genetic factors have been implicated in playing a significant role in susceptibility to eating disorders such as anorexia nervosa (AN) and bulimia nervosa (BN). Genetic variants of ghrelin, an endogenous acylated peptide that stimulates growth hormone secretion, enhances appetite, and increases body weight, have been investigated in association with eating disorders, as changes in the ghrelin/growth hormone secretagogue receptor (GHSR)/ghrelin O-acyltransferase (GOAT) system have been implicated in its pathology. Although most candidate-gene association studies have not been able to identify ghrelin gene variants as being significantly associated with either AN or BN, some ghrelin variants may be associated with BN in Japanese. Furthermore, a significant association of a GHSR gene variant with BN and that of a GOAT gene variant with AN have been found. However, there have been relatively few studies, tested variants are restricted, and sample sizes are often modest. Therefore, further studies are needed to elucidate the role of ghrelin-related gene variants in the predisposition and pathology of eating disorders.