Effects of inbreeding on reproductive losses in Kota tribe.

Abstract

Sanghvi's hypothesis on long term effects of inbreeding was tested in Kotas. Kota is a numerically small tribal population in the Nilgiri district, Tamil Nadu State, India. Consanguineous marriages are common in this tribe. A total of 95 couples were taken for this study and necessary data were collected on a set proforma. Of the 95 couples, 28 (29.5%) were consanguineously related. The inbreeding coefficient for autosomal genes is 0.022 and for sex-linked genes is 0.03. Inbreeding effects on reproductive losses were examined through an exponential regression model. Although the regression coefficient B values are positive, they are insignificant, suggesting no consistent relationship between degree of consanguinity and the reproductive losses. The estimates of genetic load is 1.8 lethal equivalents per gamete and the average B/A ratio is 5. These findings empirically support the Sanghvi's contention.