Association between 5HT2A receptor gene promoter region polymorphism and eating disorders in Japanese patients

Background: Evidence from family and twin studies suggests a genetic contri bution to the etiology of eating disorders (EDs). Recently, researchers hav e reported genetic associations between the MspI polymorphism (-1438A/G) of the promoter region of the 5HT2A receptor gene and EDs; however, reports o f evidence against these findings make the association controversial. Methods: The authors examined the prevalence of the -1438A/G polymorphism o f the 5HT2A receptor gene among 182 Japanese patients with EDs and 374 norm al control subjects. Interactions of the association of this polymorphism w ith subtypes of anorexia nervosa (AN), bulimia nervosa (BN), and various cl inical characteristics were also assessed. Results: In contrast to previous studies reporting elevated A allele freque ncies inpatients with AN, the G allele had a significantly higher frequency in patients with BN but not in patients with AN, than in control subjects. Examination of the interactions revealed that the presence of the binge ea ting and/or purging behavior and comorbid borderline personality disorder ( BPD) tended to be associated with increased frequency of the G allele. Conclusions: Though preliminary, these results can be interpreted as sugges ting that the G allele of the 5HT2A receptor gene -1438A/G polymorphism may be associated with pathological features that EDs and BPD have in common, especially disinhibition in eating behavior and personality trait. (C) 2001 Society of Biological Psychiatry.