Asok Kumar Mukhopadhyay
All India Institute of Medical Sciences, India
Title: The phenomenon of epistasis altering the odd ratio of having Alzheimer's disease and vascular dementia
Biography
Biography: Asok Kumar Mukhopadhyay
Abstract
While doing genetic polymorphism study on 80 patients of Alzheimer disease (AD) and 50 cases of Vascular dementia (VaD) recruited from cognitive disorder clinic of All India Institute of medical sciences, it was noticed that the phenomenon of gene-gene interaction or epistasis, when genes are in some specific combination, has been altering the odds ratio of having disease. This was a cross sectional, observational study with 120 controls of comparable gender and age. Polymorphism of five genes, namely ApoE genes, MTHFR-C677T, MTHFR-A1298C, IL-6 174 G/C and PON1 genes, were studied and their epistatic interactions were examined. Besides the single gene’s influence on alteration of odds ratio, it was observed that specific combination of (presence or absence) of MTHFR 677 and IL-6-174 genes, MTHFR 1298 and IL-6-174 genes, PON1 rs854560 and ApoE €4 genes , PON1 rs662 and ApoE €4 genes have been significantly altering the odds ratio of having AD, VaD or both. No epistatic interaction was observed between MTHFR677 and MTHFR 1298 genes. Since the genes like ApoE and PON1 are on different chromosomes (chromosome 19 and chromosome 7 respectively) and MTHFR and IL-6174 genes are also on different chromosomes (chromosome 1 and chromosome 7 respectively), it is of great concern how the genes which are at such a distance apart interact with each other to influence the phenotypic outcome in form of AD or VaD. These preliminary findings in Indian population attending a tertiary care hospital are stimulus for further investigating the mechanism of gene-gene interaction or epistasis.