News source: http://www.sciencemag.org/
In a hospital conference room here in Saudi Arabia’s capital, a lieutenant colonel in the Saudi army, dressed in fatigues and a black beret, stoically tells a story of genetic casualties. His and his wife’s first child, born in 2004, seemed healthy at first, but at 6 months old the baby girl could not yet sit up and barely cried. Doctors in France, where the family was living at the time, found no explanation. “We were sure that lack of oxygen” during delivery had caused brain damage, the father says.
Although their next baby, a boy, was healthy, a second girl born 5 years later had similar developmental delays. Meanwhile, the officer’s sister had given birth to six children, two healthy but four with similar medical problems: Each had crossed eyes and an IQ below 70, didn’t talk, and didn’t walk until about age 5.
Both the lieutenant colonel, who asked not to be identified, and his sister had married first cousins, who were also related. Suspicions that this close kinship played some role in their kids’ problems led the two families to this clinic at King Faisal Specialist Hospital and Research Centre (KFSHRC) and into the care of Fowzan Alkuraya, a young Saudi geneticist who had recently returned from the United States. Some months after the families gave him DNA samples, Alkuraya delivered the results: All four parents carried one copy of the exact same disease mutation, a change of a single DNA base in a gene called ADAT3. Although the mutation was harmless to the parents because each retained a working copy of the gene, their severely disabled children had inherited two faulty copies. As a result, their cells couldn’t make an enzyme that helps translate DNA into proteins.
Alkuraya’s news brought the families some measure of comfort, and hope. “It was a big relief for my wife, for me, for my sister, for everyone” to know what had gone wrong, the officer says. Hoping to break their bad genetic luck, he and his wife decided they would turn to in vitro fertilization (IVF) and use preimplantation genetic diagnosis to select embryos that inherited no ADAT3 mutation. They now have 2-year-old twins, a boy and a girl. “And they are perfectly healthy,” the father says.
The officer’s family is one of hundreds that have come to Alkuraya, 39, who may be the country’s leading genetics sleuth. His work is part of a boom in human genetics research in Saudi Arabia over the past decade, which has culminated in a Saudi version of a human genome project, called the Saudi Human Genome Program (SHGP). Largely because many Arabs marry cousins or other close relatives, the country, like others in the Middle East, has an increased rate of inherited genetic diseases—nearly double the rate in Europe and the United States and 10 times higher for certain disorders, according to some estimates. As a result, the country has long drawn Western scientists eager to bag disease genes new to science. But Alkuraya and other geneticists here at KFSHRC are bringing such research home. Read more >>