Time magazine reports that two Fundamentalist Church of the Latter Day Saints of Jesus Christ (FLDS) families, who are ancestors of many of the polygamist sect members in Texas, have handed down a recessive gene for a severe form of mental retardation called Fumarase Deficiency.
The birth defect has increased within the FLDS community since 1990, when it was first identified by a now retired pediatric neurologist, after an FLDS member in Arizona brought her severely mentally disabled son to see him. The child also had a sister with cerebral palsy, as well as Fumarase Deficiency syndrome.
"The birth defect — an enzyme deficiency — causes severe mental retardation, epilepsy and disfigurement of features," Time reports. "The retardation is in the severe range — an IQ around 25," the pediatric neurologist Dr. Theodore Tarby says. "Afflicted children are missing portions of their brain, often cannot sit or stand, and suffer grand mal seizures and encephalitis. Language skills are nonexistent or minimal. "
Until 1990, Tarby says he knew of only 13 cases of Fumarase Deficiency worldwide, according to Time. The intermarriage within the FLDS community, in which many first cousins marry, causes the high incidence of the birth defect.
"If you have two parents with the gene," Tarby says, "you are going to have a one-in-four chance of having a child afflicted with it."
Texas officials will not release any medical information about the 416 children in their custody, Time said, but one mother, identified only as Sally on CNN's "Larry King Live," described her son as "handicapped" and needing hourly care.
"One of the mothers raised concerns about her child who had Down Syndrome," Texas Department of Family and Protective Services (TDFPS) spokesman Greg Cunningham told Time in an e-mail. "That child has had a medical evaluation and has had one-on-one care."
"The FLDS community, by and large, rejects the idea that Fumarase Deficiency is caused by genes," according to Dr. Tarby. "They have their mythology about the condition. They think it's something in the water, or something in the air."
