Adrenergic alpha2A receptor gene and response to methylphenidate in attention-deficit/hyperactivity
T L da Silva1, T G Pianca, T Roman
1ADHD Outpatient Clinic, Child and Adolescent Psychiatric Division, Hospital de Clínicas de Porto Alegre, Federal University of Rio Grande do Sul, Rio Grande do Sul, Brazil.
Abstract:
An association between ADRA2A -1291 C > G polymorphism and response to methylphenidate in inattentive symptoms was previously suggested in children with ADHD. No investigation specifically assessed this association in ADHD-inattentive type (ADHD-I). In this naturalistic pharmacogenetic study, 59 subjects with ADHD-I from a non-referred sample were treated with short-acting methylphenidate and genotyped for ADRA2A -1291 C > G polymorphism. The primary outcome measure was the inattentive subscale of the SNAP-IV applied by a child psychiatrist blinded to genotype at baseline and first month of treatment. Children and adolescents with the G allele showed significantly lower inattentive scores with MPH treatment at the first month of treatment than subjects without the G allele (n = 59; F = 6.14; p = 0.016). We extended to ADHD-I previous findings suggesting the influence of the G allele at the ADRA2A -1291 C > G polymorphism on the improvement of inattentive symptoms with methylphenidate in children with all ADHD subtypes.
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