Surname Endogamy among the Brahmin of India

Abstract

Endogamy has been a strong influence on Hindu society over the centuries and most of the 75,000 subcastes or subgroups of India's complex social stratification system practise endogamy, while the further divisions within these subcastes, called gotras, are required to marry exogamously. The present study focuses on three socioculturally isolated, highly endogamous groups, to study the effect of endogamy on genetic microdifferentiation. The groups are all subdivisions or classes of the Brahmin or priest caste, namely Bhargavas and Chaturvedis and Kanyakubja and Sanadhaya Brahmin, and all groups practise patrilineal surname endogamy. Two-generation pedigrees were drawn up and microdifferentiation was estimated using parameters like mean concordance, i.e. within-gotra marriages in Bhargavas and Chaturvedis, F_IT (the inbreeding coefficient or inbreeding-like effect due to endogamy), F_ST (within-group a priori kinship) and R_ST (reduced variance of the mean value of within-group a priori kinship). Our results indicate that there is an increase in same-gotra marriage showing that these groups are in fact not following the strict rule of exogamy. This is highest among Chaturvedis (17.1 percent) as compared to Bhargavas (11.2 percent), Kanykubja Brahmins (13.4 percent) and Sanadhaya Brahmin (16.92 percent). The F_ST is almost the same in all the populations over two generations; however, it is slightly lower among Bhargavas and highest in Brahmin indicating that although these populations follow endogamy at surname level they are exogamous at gotra/kuldevi level. The same is indicated by F_IS, which shows that in spite of strict endogamy there is no inbreeding-like effect in these populations. R_ST measures variance among populations and our results reveal that these populations are distinct from one another.