The association of A-1438G and T102C polymorphisms in HTR2A and 120 bp duplication in DRD4 with alcoholic dependence in a northeastern Brazilian male population

Abstract Background Around the world, 3.3 million deaths are related to alcohol abuse. In Brazil, there are more than 4 million people with this behavior. Alcohol Dependence (AD) is a complex psychiatric disorder characterized by excessive alcohol consumption influenced by genetic and environmental factors. HTR2A and DRD4 are genes related to the serotonergic and dopaminergic systems and alterations in their sequences are associated with the etiology of AD. Our work analyzed the association between A-1438G (rs6311) and T102C (rs6313) polymorphisms in HTR2A and 120 bp duplication in DRD4 with the susceptibility to AD in that group of people. Methods Blood samples were collected from 300 men from Northeastern Brazil (150 alcohol-dependents and 150 controls). After DNA extraction, the determination of HTR2A and DRD4 genotypes was performed through PCR-RFLP method. The allele and genotype frequencies and association of polymorphisms with AD were determined using chi-square and Fisher\u0027s exact test, as well as, odds ratio (OR) with confidence interval of 95%. Value of p  Results Significantly, the low education, intake of doses per day, smoking and a positive family background of alcoholics were predominant in alcoholics patients than controls (p  Conclusion Therefore, we suggest that the homozygous and heterozygous genotypes of the A-1438G and T102C polymorphism in the HTR2A gene, together with the positive family AD history, may be associated with the development of AD in the northeastern Brazilian male population displaying a dominant inheritance model. Further work is strongly encouraged to confirm the role of these polymorphisms in AD.