Association of variable number of tandem repeats (VNTR) and T941G polymorphism of monoamine oxidase (MAO-A) gene with aggression in Pakistani subjects|
Sarwar, Sumbal; Shabana & Hasnain, Shahida
Background: Human behavioral traits are known to be significantly heritable. Certain individuals have a greater tendency
of negative behavioral aspects including aggression. The quest to identify tunderlying genetic causes has led to identification
of a number of genetic markers, one of them is the monoamine oxidase-A (MAO-A) gene.
Objective: We aimed to genotype a variable number of tandem repeats (VNTRs) in the promoter region and a functional
SNP within this gene (T941G, dbSNP ID: rs6323) in the recruited cohort of 482 subjects.
Methods: After DNA isolation, genotyping was done by PCR-RFLP and the results were confirmed by sequencing.
Results: For VNTRs, the results showed, highest frequency of 3.5 repeats in males and 4 repeats in females in the promoter
region. The genotype frequencies for the SNP in cases were GG=16.3%, TG=20.6% and TT=63.1%, while in controls, the
frequencies were GG=12.7%, TG=6.3%, and TT=81.0%. The allele frequencies were significantly different between cases
and controls (p=0.015; OR=1.51; CI=1.085-2.102).
Conclusion: The selected VNTR and SNP appeared to be significantly associated with aggression. These VNTRs and SNP
have not been studied previously in the Pakistani population, hence they represent a unique ethnic group. These results,
however, would have to be replicated in larger cohorts.
Aggression; MAO-A gene; VNTRs; T941G; rs6323; Pakistan.