NEW DELHI : Variation in a genetic mutation among Indians may be the main reason behind the difference in the death rates due to COVID-19 across various states of the country, says a study that could inform new policies for controlling the novel coronavirus pandemic.An international team, led by researchers at Banaras Hindu University (BHU) in Uttar Pradesh, analysed mutations in the gene responsible for the expression of the Angiotensin Converting Enzyme 2 (ACE2), a protein on the surface of cells which is believed to act as a gateway for the novel coronavirus into the human body.Recent studies have effectively demonstrated that the ACE2 is encoded by a gene located on the X chromosome.In the journal Frontiers in Genetics, the researchers.