Intra-family unions contribute to 10% of diabetes cases among South Asians, as per a recent study. Marriages within blood relatives, a practice prevalent in South Asian communities, particularly involving second cousins or closer relatives, known as consanguinity, are implicated in the elevated risk of Type 2 diabetes.

While South Asian communities account for 8% of diagnosed diabetes cases, exceeding their 4% population representation, the underlying factors were unclear. To investigate the impact of consanguinity on health, researchers from the Wellcome Sanger Institute and Queen Mary University of London analyzed genetic data from over 400,000 individuals in Britain.

The study identified 12 diseases and disorders linked to consanguinity, including Type 2 diabetes, asthma, and post-traumatic stress disorder. Consanguineous marriages were found to contribute to approximately 10% of Type 2 diabetes cases among British Pakistanis and around 3% among British Bangladeshis. Additionally, it was estimated to be responsible for 8% of asthma cases in British Pakistanis and 2% in British Bangladeshis.

Around 33% of individuals of Pakistani and Bangladeshi descent in Britain were offspring of second cousins or closer, compared to just 2% of individuals of European descent. Marrying close relatives increases the risk of passing on harmful gene mutations within families.

Despite the health risks associated with consanguinity, the study emphasizes the need to balance these concerns with the positive social aspects of the practice, such as family bonding. The researchers highlight that lifestyle factors, including lack of exercise, smoking, and obesity, have a more significant impact on health disparities than consanguinity.

Coun Ahsan Khan, chair of the Genes & Health community advisory board, emphasized the importance of culturally sensitive approaches in health research, acknowledging the delicate balance between social benefits and potential risks. The research aims not to pass judgment on consanguinity but to guide future studies for a better understanding of associated diseases and their underlying biology. The findings were published in the journal Cell.