A family-based association study of the HTR1B gene in eating disorders.

OBJECTIVE To explore the association of three polymorphisms of the serotonin receptor 1Dβ gene (HTR1B) in the etiology of eating disorders and their relationship with clinical characteristics. METHODS We analyzed the G861C, A-161T, and A1180G polymorphisms of the HTR1B gene through a family-based association test (FBAT) in 245 nuclear families. The sample was stratified into anorexia nervosa (AN) spectrum and bulimia nervosa (BN) spectrum. In addition, we performed a quantitative FBAT analysis of anxiety severity, depression severity, and Yale-Brown-Cornell Eating Disorders Scale (YBC-EDS) in the AN and BN-spectrum groups. RESULTS FBAT analysis of the A-161T polymorphism found preferential transmission of allele A-161 in the overall sample. This association was stronger when the sample was stratified by spectrums, showing transmission disequilibrium between the A-161 allele and BN spectrum (z = 2.871, p = 0.004). Quantitative trait analysis showed an association between severity of anxiety symptoms and the C861 allele in AN-spectrum participants (z = 2.871, p = 0.004). We found no associations on analysis of depression severity or preoccupation and ritual scores in AN or BN-spectrum participants. CONCLUSIONS Our preliminary findings suggest a role of the HTR1B gene in susceptibility to development of BN subtypes. Furthermore, this gene might have an impact on the severity of anxiety in AN-spectrum patients.