Family-based association study between the brain derived neurotrophic factor (bdnf) gene and the attention deficit hyperactivity disorder in a Mexican population

Abstract

The attention deficit hyperactivity disorder (ADHD) is a common neuropsychiatric disease in infancy and adolescence, its world prevalence in the general population is high 3.4%. There is genetic evidence that consistently supports the polygenic nature of ADHD with a heritability estimated between 75% and 91%; literature proposes that the brain derived neurotrophic factor (BDNF) is a candidate gene that participates in the ADHA pathogenesis. One of the most studied polymorphisms is the Val66Met. The aim of this study was to determine a family-based an association between the rs6265, rs122,733,63 and rs110,301,19 polymorphisms of the BDNF gene and the ADHD in a Mexican population. The ADHD diagnose was performed by a pedopsychiatrist utilizing the diagnostic and statistical manual of mental disorders (DSM-V) who selected 35 patients; along with the biological parents, a total of 105 individuals grouped in family-trios (mother, father and ADHD patient) were studied. Of the 35 probands, 32 were men and 3 were women (average age 7.7 years; age range 4–14 years). Subsequently, no statistically significant association was observed between the BDNF gene polymorphisms and the ADHD etiology in Mexican families: rs6265 (χ² = 1.33; P = 0.24); rs122,733,63 (χ² = 1.33; P = 0.24); rs110,301;19 (χ² = 0.66; P = 0.41). Furthermore, no preference of transmission was observed for any of the haplotypes. In conclusion, it was not possible to prove any association between the BDNF gene polymorphic variants and ADHD in a Mexican population. Future studies comprising larger samples are necessary to determine the potential role of the BDNF gene in ADHD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.