Consanguinity, inbreeding and genetic load in salis: A sub divided population of Andhra Pradesh, South India

Abstract

Aims and Objectives: The objective of the present study is to assess the genetic composition of the two subgroups of Salis and the extent of genetic differentiation among them with the help of various demographic and genetic variables. Materials and Methods: A total of 520 couples belonging to two sub-groups namely, Padmasalis and Pattusalis residing in and around Visakhapatnam and Vizianagaram of Andhra Pradesh were included in this study. Demographic data pertaining to consanguinity and reproductive histories were obtained. Statistical analysis was done using SPSS v 19 software. Results: Out of 520 married couples, 180 women had practiced consanguineous marriages (34.62%) and 340 women had adapted to non-consanguineous (65.38%) marriages. The overall consanguinity is more among the Padmasalis (36.98%) than among the Pattusalis (32.16%). However, the difference between the two groups is not statistically significant. The coefficient values for autosomal genes is higher in Padmasalis (0.0354) than the Pattusalis (0.0279). Likewise, the coefficient values for sex -linked genes is higher in Padmasalis (0.0340) than the Pattusalis (0.0319). In the present study population the inbreeding load ( B) obtained for Pattusalis was positive (0.8850) but in Padmasalis it was negative ( -2.5714) indicating an increase in survival of individuals with increased homozygosity. The random load (A) in Pattusalis was 1.5944 and in Padmasalis it was 1.9290. The pooled data of Salis recorded a negative B value indicating an increase of fitness of offspring in comparison to the fitness of their parental generations. Conclusion: The frequency of consanguinity was found to be high in Salis. The findings are in concurrence with the earlier reports of high prevalence of consanguineous marriages in South India. Female education, socio-economic status and parental decisions in marriages may be the reasons.