Heterogeneity of ApolipoproteinE polymorphisE and its Isoforms in Five caste groups of Punjab, India

Abstract

Genetic polymorphism of ApolipoproteinE is controlled by three connon alleles(E2,E3 and E4) and some rare alleles (e.g. El, E4v etc;) at Apo E structural gene locus and may be demonstrated by Iso-electric Focussing, Density gradient poly-acrylamide gel electrophoresis and Imunoblotting techniques et;. The common ApoE isoform E2 (arg158-cys) and E4 (cys112-arg) differ functionally from the parent E3 isoform, explaining their effects on the normal variation of Plasma Lipoprotein concentrations and their association with Hyperlipidemic conditions. Apolipoprotein genotypes were determined in five endogamous caste groups in a sample of 150 Indians from Punjab. ApoE have been observed at respective allele frequencies 0.077, 0.807 and 0.115 in these population groups of Banias, 0.050, 0.825 and 0.125 in Brahmins, 0.057, 0.846 and 0.097 for Jat Sikhs, 0.060, 0.800 and 0.140 in Khatris and 0.035, 0.839 and 0.125 for mixed group ‘Others’. Apo E3 (ApoE3,3 and ApoE3,4) subjects had higher frequencies than ApoE4 (ApoE4,3 and ApoE4,4) and ApoE2 (ApoE2,2 and ApoE3,2) subjects in all the groups studied suggesting the low prevalence of Alzheimer's disease and CHD's. The estimated ApoE allele frequencies were combined with data from other studies of the World to outline the total map of ApoE allele frequency distribution from Europe to Asia.