DNA methyl transferase (DNMT) gene polymorphisms could be a primary event in epigenetic susceptibility to schizophrenia

PLoS One. 2014 May 23;9(5):e98182. doi: 10.1371/journal.pone.0098182. eCollection 2014.

Abstract

DNA methylation has been implicated in the etiopathology of various complex disorders. DNA methyltransferases are involved in maintaining and establishing new methylation patterns. The aim of the present study was to investigate the inherent genetic variations within DNA methyltransferase genes in predisposing to susceptibility to schizophrenia. We screened for polymorphisms in DNA methyltransferases, DNMT1, DNMT3A, DNMT3B and DNMT3L in 330 schizophrenia patients and 302 healthy controls for association with Schizophrenia in south Indian population. These polymorphisms were also tested for subgroup analysis with patient's gender, age of onset and family history. DNMT1 rs2114724 (genotype P = .004, allele P = 0.022) and rs2228611 (genotype P = 0.004, allele P = 0.022) were found to be significantly associated at genotypic and allelic level with Schizophrenia in South Indian population. DNMT3B rs2424932 genotype (P = 0.023) and allele (P = 0.0063) increased the risk of developing schizophrenia in males but not in females. DNMT3B rs1569686 (genotype P = 0.027, allele P = 0.033) was found to be associated with early onset of schizophrenia and also with family history and early onset (genotype P = 0.009). DNMT3L rs2070565 (genotype P = 0.007, allele P = 0.0026) confers an increased risk of developing schizophrenia at an early age in individuals with family history. In-silico prediction indicated functional relevance of these SNPs in regulating the gene. These observations might be crucial in addressing and understanding the genetic control of methylation level differences from ethnic viewpoint. Functional significance of genotype variations within the DNMTs indeed suggest that the genetic nature of methyltransferases should be considered while addressing epigenetic events mediated by methylation in Schizophrenia.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • DNA (Cytosine-5-)-Methyltransferases / genetics*
  • Female
  • Genetic Predisposition to Disease / epidemiology*
  • Genotype*
  • Humans
  • India / epidemiology
  • Male
  • Middle Aged
  • Polymorphism, Single Nucleotide*
  • Risk Factors
  • Schizophrenia / enzymology
  • Schizophrenia / epidemiology*
  • Schizophrenia / genetics*
  • Sex Factors

Substances

  • DNA (Cytosine-5-)-Methyltransferases

Grants and funding

KRS was supported by Council for Scientific and Industrial Research (CSIR) New Delhi through a research fellowship. MB was supported through intramural project support from Rajiv Gandhi Center for Biotechnology (RGCB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.