Association of the SLC6A4 gene 5HTTLPR polymorphism and ADHD with epilepsy, gestational diabetes, and parental substance abuse in Mexican mestizo children

Abstract

Introduction. Attention deficit hyperactivity disorder (ADHD) is one of the most common neuropsychiatric conditions in childhood and a multifactorial condition attributable to genetic and/or environmental influence. Allelic variants in the serotonin transporter gene (SLC6A4) have been associated to lower transcriptional efficiency, changes in serotonin concentration in several brain regions, and ADHD development. Objective. To identify the association between the SLC6A4 alleles and ADHD diagnosis and risk factor phenotypes in children from a Mexican mestizo population. Method. In this study, 134 unrelated children were included and evaluated for ADHD, genotypification for the 5HTTLPR polymorphism, and identification of multiple phenotypes from their clinical records and family background for association analysis. Results. The following distribution of genotypes was observed: 23% SS, 49% SL, and 28% LL. From the phenotypes evaluated in the present study, gestational diabetes mellitus (p = .045), history of epilepsy (p = .047), and parental substance abuse (p = .033) showed an association with ADHD development in regression analysis along with the S variant. Discussion and conclusion. Results suggest that interaction of the S allele and some of the phenotypes analyzed may play a relevant role in the development of ADHD in the studied population.

The role of 5-HTTLPR in autism spectrum disorder: New evidence and a meta-analysis of this polymorphism in Latin American population with psychiatric disorders

“…Recognizing the under-representation of Latin American population in studies aimed to understand the role of 5-HTTLPR on worldwide [26,27,29], here we present a meta-analysis including articles which evaluate this polymorphism in Latin American individuals with psychiatric disorders as ASD, bipolar disorder, major depressive disorder, obsessive compulsive disorder, attention deficit hyperactive disorder, schizophrenia, dysthymia, anxiety disorder and suicide [37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. Although the S allele has been associated with increased risk for psychiatric disorders [16][17][18][19][20][21]55], our meta-analysis revealed no significant heterogeneity among studies, no publication bias and failed to find an association between 5-HTTLPR and a risk for psychiatric disorders.…”