HbE genotypes and fertility: a study on a Tibeto-Burmese population in Upper Assam, India.

BACKGROUND

The north-eastern states of India in general and the state of Assam in particular appear to be areas with a very high incidence of HbE, with the highest frequency of the allele observed among the Kachari population.

AIM

In the present study a Tibeto-Burmese speaking population of Assam, India has been studied with regard to haemoglobin E (HbE) and to examine the role of different HbE genotypes on fertility.

SUBJECTS AND METHODS

Detailed reproductive histories and socio-economic data were collected from 159 unrelated Mishing (a Tibeto-Burmese population) couples initially. Haemoglobin typing was done by restriction digestion to detect wild type (HbA/HbA), heterozygotes (HbA/HbE) and homozygotes (HbE/HbE).

RESULTS AND CONCLUSION

The HbE gene frequency for the total 318 individuals was 0.4623. The results suggest that HbE homozygosity is associated with a higher pregnancy rate. Mothers homozygous for HbE also have more live births in spite of having more spontaneous abortions. The study shows that HbE homozygous women may be getting an advantage up to the point of conception but beyond that various factors come into play to increase miscarriage and infant mortality and that the socio-economic factor is one important reason behind this.