Investigating epistasis in suicide ideation using multifactor dimensionality reduction: A population-based study from North India

Abstract

BackgroundConsidering the complex nature of suicide ideation (SI), this study aimed to understand the association of SI with selected gene polymorphisms (HTR1A, KIAA0319, NRG1, CYP2C19, TPH1, HTR1B, PTN, and CACNA1C) and their epistatic interactions using Multifactor Dimensionality Reduction (MDR) analysis. MethodsThe study was carried out among a total of 243 individuals of either sex in the age group 35–75 years belonging to Haryana, North India. Data pertaining to socio-demographic variables were collected using an interview schedule. Screening for SI was done using the Patient Health Questionnaire-9 (PHQ-9) item 9. Genotyping was done using Human Omni BeadChip from Illumina during the initial discovery phase and Illumina Golden Gate Assay during the final phase. Statistical analysis was done using SPSS version 20, MS-Excel, and MDR 3.0.2. ResultsThe AA genotype of KIAA0319 rs2760157 was found to be significantly higher among suicide ideators. However, SI was not found to be independently associated with any of the selected SNPs. In MDR analysis, the three-loci model with HTR1A, HTR1B, and CYP2C19 SNPs was the best model for predicting SI and KIAA0319 rs2760157 showed a strong independent effect in predicting SI (though these results did not reach the level of statistical significance). ConclusionsThe role of synergistic interactions among HTR1A, HTR1B, and CYP2C19 SNPs in SI and the association of SI with KIAA0319 polymorphisms should be explored in future studies.