Brain derived neurotrophic factor gene Val66Met and -270C/T polymorphisms and personality traits predisposing to anorexia nervosa.

OBJECTIVES: Polymorphisms in BDNF gene has been proposed, as susceptibility loci for stress-related psychiatric disorders. Several lines of molecular and biochemical evidence point to the role of BDNF in anorexia nervosa (AN). Personality traits may constitute the intermediate phenotypes between genes and vulnerability to AN.

METHODS: BDNF Val66Met and -270C/T polymorphisms were genotyped in 149 patients with AN and 100 healthy control females. Temperamental traits in all subjects were measured with Temperament and Character Inventory. First in case-control analysis, we assessed, if analyzed genotypes confer risk for AN. Next, the association of BDNF gene variants with personality dimensions in patients and control subjects was analyzed.

RESULTS: No significant differences between patients with anorexia nervosa and controls in frequency of genotypes and alleles were observed. AN patients with Met allele showed higher Harm avoidance (Anova F=4.70; p=0.03) than Val/Val homozygotes. AN patients, who carried the T allele of BDNF -270C/T polymorphism showed higher Persistence (Anova F=4.04; p<0.05) and Harm avoidance (Anova F=7.93; p=0.006) than C/C homozygotes, however after correction for multiple testing only the latter association remained statistically significant. No significant relationship between Val/Met 66 genotype and -270C/T genotype with personality was observed in healthy females.

CONCLUSIONS: These results may suggest, that BDNF -270 C/T polymorphism may influence the personality trait associated with higher risk of AN.

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