A fundamentalist Mormon sect living along the Nevada-Arizona border has a serious problem with a rare genetic disorder, because everyone is closely related to everyone else:
“With polygyny you’re decreasing the overall genetic diversity because a few men are having a disproportionate impact on the next generation,” says Mark Stoneking, a geneticist at the Max Planck Institute for Evolutionary Anthropology, Germany. “Random genetic mutations become more important.”
In isolated communities, the problem is compounded by basic arithmetic: if some men take multiple wives, others can’t have any. In the FLDS, a large proportion of men must be kicked out as teenagers, shrinking the gene pool even further.
Which brings us to the good news. Since inbreeding tends to uncover “recessive” mutations that would normally remain in hiding, studying these communities has helped scientists to identify many disease-causing genes. That’s because genetic information is useless on its own. To be meaningful to medical research, it must be linked to information about disease. In fact, more human disease genes have been discovered in Utah – with its Mormon history – than any other place in the world.
It’s not the legacy Brigham Young expected, but in the end, it’s possible that the controversial practice might have some unintended positives.
Religion, man. Religion.