The whole thing is just friggin’ creepy.

Fifteen years ago, a strange-looking child suffering from severe physical maladies and acute retardation was brought into the office of Dr. Theodore Tarby. The pediatric neurologist regularly deals with a wide range of serious childhood diseases as a doctor with the state-funded Children’s Rehabilitative Services in Phoenix. Tarby says he quickly realized he was dealing with a very unusual condition that he could not diagnose. He prepared urine samples and sent them to the University of Colorado Science Center’s Dr. Steve Goodman, a professor of pediatrics who runs a laboratory that detects rare genetic diseases. Goodman soon made a startling discovery: Tarby’s young patient was afflicted with an extremely rare disease called fumarase deficiency. – From Phoenix New Times

Nearly everyone in Colorado City, Arizona, and the adjacent town of Hildale, Utah, was a member of a fundamentalist Mormon sect that practices polygamy and had long encouraged multiple marriages between close relatives. By the late 1990s, Tarby and his team had discovered fumarase deficiency was occurring in the greatest concentration in the world among the fundamentalist Mormon polygamists of northern Arizona and southern Utah. Of even greater concern was the fact that the recessive gene that triggers the disease was rapidly spreading to thousands of individuals living in the community because of decades of inbreeding. Fast-forward to the present: About half of the 8,000 people living in the towns are blood relatives of two of the founding families that settled in the 1930s on the desolate high desert plateau against the base of the Vermillion Cliffs. Religious leaders control all marriages in the community, and many of these relatives have married or likely will marry in the future. Some of these marriages will include parents who both are carriers of the fumarase deficiency gene, making it certain that more children will be afflicted with the disease. – From Phoenix New Times