Genes of a desert peopleIn the last few decades, the Jewish world has begun paying attention to so-called Jewish genetic diseases, but one Israeli researcher is seeking clues to devastating genetic illnesses that affect another Middle Eastern population: Bedouins.Among the sidelights of the U.N. Deserts and Desertification conference, attendees paid a visit to Dr. Ohad Birk, head of the Morris Kahn Laboratory of Human Genetics at the National Institute for Biotechnology at Ben-Gurion University of the Negev. He is also the director of a related institution, the Genetics Institute at Soroka University Medical Center. As part of his genetic research, Birk has been working with Dr. Khalil Elbedour, a Bedouin physician from Israel, to identify the diseases that have struck hundreds of children in the Negev Bedouin population in the last decade. The project had strong support from Rivka Carmi, acting president of the university when the program was launched. (She has since become its president.) Carmi, a physician and genetics professor herself who has been living and practicing in the Negev region since she graduated from medical school, told visiting journalists that part of her vision for "transforming the Negev" included improving life for the region's large Bedouin population. Some 500 Bedouin students, half of them women (a fact worth noting in a highly male-dominated culture), attend the university. But many Bedouin children are born with rare, severe illnesses and deformities. The reason, Birk said, is that under Bedouin tradition, first cousins often marry. When the population lived a nomadic desert life, the tradition helped to keep extended families together and strengthen the family unit. But today - when some 65 percent of the Negev Bedouins still marry first or second cousins - the result has been to increase the odds that both parents will carry the same mutation, upping the chances for having a child with a genetic disease or deformity. In addition, Birk said, many husbands have two or three wives, often from the same extended family, and the Negev Bedouins have an average of eight to 10 children, all factors that work toward increasing the prevalence of genetic diseases. Birk and Elbedour, along with Dr. Izzeldin Abuelaish, a Palestinian physician from the Gaza Strip, are trying to do something to change that. Their approach is two-pronged: First, they try to identify the genes that cause the diseases, many of which kill children in the first few years of life or leave them permanently disabled. Blindness and severe mental retardation are particularly common. So far, eight new mutant genes, plus new mutations in previously identified genes that were associated with diseases, have been found. The second approach is to offer premarital genetic counseling and prenatal testing to Bedouin couples - not an easy task in a closed society of proud individuals who don't take well to meddling by outsiders. Still, Birk and the other doctors are working with Muslim leaders to get across the message about genetic counseling and about the dangers of marrying close relatives. Some of it, at least, seems to be working. Birk said that in the last year more than 20 couples decided to end pregnancies after prenatal testing showed that their fetuses carried severe terminal diseases. In addition, the research being carried out in Birk's lab may have implications for more common diseases that have a genetic component, such as diabetes and asthma, and may lead to the creation of drug therapies for those and other diseases. With that revelation, Birk said, "the pharmaceutical companies are beginning to pay attention." - P.Y. |
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