Researchers have found that 3,222 British people who have Pakistani heritage commonly have mutations in 140 genes that stop those genes from working. The scientists observed that among those 821 participants, 781 genes were determined to no longer be functioning. This was done by analyzing those people's exomes, which is part of the genome and made up of exons that codes for proteins. Previous research has shown that some genes can be missing in healthy people, but 422 of the genes looked at in this particular study are ones that scientists did not know that people could healthily live without. This experiment proposes that uncommon mutations that knock out both copies of a specific gene aren't always automatically a problem. In the United States and England, analysts compared the health records from people in the study with over 1,500 people without the mutation. They discovered that those people with unique mutations were no more susceptible to health problems than those without.
A woman had mutations related to a gene that is important for meiotic division, specifically forming the egg and sperm, the PRDM9 protein. She later gave birth showing that she was, in fact, still fertile. Researchers believe that this could be due to a compensatory mechanism, which could perplex the pursuit for genes that cause rare genetic disorders.
This research really surprised me because having mutations in a few genes sounds like it would seem okay, but mutations in 140 sounds extreme. It sounds kind of crazy that a person can still be completely healthy while 140 of their genes aren't working. Since all the people in the study have the same heritage, maybe this event can have occurred because of an evolutionary factor or their external environment somehow modified their genes.