HYDERABAD: Marrying within the same caste is harmful for health of the offspring of such couple, points out a study conducted by Center for Cellular and Molecular Biology, Hyderabad. The study busts commonly held assumption that only marrying within close relatives can cause genetic problems.
The report found out that even two people, not related to each other but belonging to same community, caste or tribe, if they marry each other, stands at the risk of transmitting the genetic defects in their DNA – a result of age old endogamy practice – to their offspring.
The study also raises the question of whether widely prevalent diseases in India were due to the practice of marrying within the same caste, community or tribe.
A study by a team of 17 scientists from various institutes led by Dr K Thangaraj of CCMB has found that the chances of diseases occurring in children due to genetic defects from parents, also known as recessive diseases, is very high in Indian communities because of endogamy, practice of marrying within the same community or caste in the Indian scenario.
The study was conducted on genome wide data collected from 2,800 individuals belonging to 260 communities from South Asia, around 80 percent of which were from India.
As part of study, the Identity by Descent (IBD) score was calculated for all 260 communities. IBD score gives an understanding of how vulnerable a population is to recessive diseases.
Shockingly, it was found that IBD scores of Indian communities was higher than that of even Ashkenazi Jews who are known for marrying in close communities among whom high prevalence of recessive diseases has been proven.
The report further found out that there was a high risk of recessive diseases and genetic defects, being passed on through generations, not "getting diluted". IBD scores of 14 castes from India with populations above one million reportedly were higher than Ashkenazi Jews.
It was found that IBD score of Gujjar community was 11.6 times higher than the Ashkenazi Jews. Similarly IBD score of members of Reddy and Vyshya castes was higher than Ashkenazi Jews by 2 and 1.2 times. IBD score was 9.5 times, 9.2 times and 2.4 times higher among members of Pattapu Kapu, Vadde and Kshatriya Aqnikula castes of Andhra Pradesh.
Dr Thangaraj suggested that in future there might be organizations which might provide services of providing genetic faults in the couple from same caste which desires to get married and the probable effect it might have on their child.