Apolipoprotein E allele frequencies in a South African Indian female population

Coronary heart disease is common amongst South Africans of Indian (Asian) ancestry. As part of an investigation into risk factors in premenopausal and post-menopausal Indian nurses, we determined the apolipoprotein E genotype by means of restriction isotyping on 173 healthy nurses between the ages of 25–55 years. The apolipoprotein E allele frequencies on 346 chromosomes were: ε2, 1.2% (95% confidence interval 0.06-2.66); ε3, 87.6% (95% confidence interval 84.1–91.1 and ε4, 11.3% (95% confidence interval 7.94-14.60). No ε2/2 homozygotes were encountered. Our results demonstrate an extremely low frequency of the ε2 allele, a low-normal apo ε4 and a high ε3 allele frequency. It is unlikely that apolipoprotein E polymorphism contributes to the high incidence of coronary heart disease in this population.