The Disastrous Genetic Consequences Of Decades of Polygamy

This article paints a picture of the genetic effects of decades of polygamy, by looking at the population of the American state Utah. It is in Utah where the leader of the Mormon Church, Brigham Young, proclaimed in the mid-19th century that men should have multiple wives.

Some of the consequences of that event were observed in the same town in the 1990s by a doctor who came across a number of children with a very rare disease, which was diagnosed as fumarase deficiency, which causes severe physical and mental disability. All the children were coming from the same region on the Arizona-Utah border, known as Short Creek, where the polygamous Mormons had moved at some point in history. The deficiency is very rare because “it’s recessive — it only develops if a person inherits two faulty copies of the gene, one from each parent.”

And this is where polygamy takes the stage again, because in time it reduces the genetic diversity, so that only a few men have a disproportionate influence on the generations to come. In Short Creek, for instance, 75 to 80% of the people are blood relatives of the community’s founding fathers.

On a lighter note, the article points out the positive thing about inbreeding and recessive mutations — that scientists could identify many disease-causing genes and use that knowledge in their medical research.