Is there a Link Between Anxiety, Depressive Disorders and 5HT 2A Receptor Gene Polymorphism? – Study from A Conflict Area, India-controlled Kashmir
BACKGROUND: 5 HT-2A receptor gene polymorphisms are associated with various psychiatric disorders, including anxiety and depression. However, no study has investigated 5HT 2A gene polymorphisms in anxiety and depression in a distressed society such as a conflict area. To study 5HT-2A -1438 A/G single nucleotide polymorphism in depression and anxiety disorders in India-controlled Kashmir.
METHODS: Thirty patients with depression disorders, 31 patients with anxiety disorders, and 40 unrelated healthy volunteers (controls) were studied in a case-control study design. Polymorphism was determined using polymerase chain reaction and agarose gel electrophoresis after digestion with the restriction enzyme MspI. Genotypes and allele frequencies were compared using chi square and Fischer’s exact tests, and p value of <0.05 was considered to be statistically significant.
RESULTS: The mean±standard deviation of age for the anxiety, depression and control groups was 33.5±11.7, 32.4 ± 9.9 and 29.7 ± 10.1 respectively and was not statistically significant (p= 0.32). In the anxiety group, GG genotype (41.9 %) was significantly more prevalent (p= 0.045) than the control group (17.5%). Similarly, depression group had higher prevalence of GG genotype (50%) (p=0.004) than the control group (17.5%). Comparison of allelic frequencies found a statistically significant excess of G allele in the depressive group (68.3%) as compared with the control group (36.2%) (P ≤0.0001, OR=3.8 (1.9 to 7.7).
CONCLUSION: In a conflict area, we found that the -1438 A/G single nucleotide polymorphism in the promoter region of 5HT-2A gene was associated with anxiety and depressive disorders. Our findings confirm the role of this locus in psychiatric disorders and further show that the association remains robust in a distressed society.