BEERSHEVBA, ISRAEL — Jews of Indian origin are, for the first time, taking control of a genetic mutation linked to sight problems that can’t be rectified with spectacles.
Indian Jews living in Israel have their roots in either Mumbai or Cochin, and 1 in 10 Jews from Mumbai families carries a recessive gene that, when passed on to offspring from both parents, causes a disorder affecting both short- and long-range vision. The mutation was discovered a year ago by Ohad Birk and his teams at the Genetics Institute at Soroka Medical Center and the Morris Kahn Laboratory of Human Genetics at Ben-Gurion University. It’s just one discovery among many in the prominent Israeli geneticist’s growing body of research focusing on Jewish populations of non-Ashkenazi heritage.
It was through a random encounter in southern Israel that Birk and his team realized that they were dealing with a widespread genetic mutation. They started searching for genetic markers after an Indian-Jewish family showed up at the Soroka Medical Center with a sight problem. “The ophthalmologist who was part of our team happened to go shopping, and at the counter was a nice Indian girl whose eyes were like the family’s,” Birk recalled. Her eyes, like theirs, moved very quickly. Now suspecting that this could be a disorder affecting many families, the researchers set out to find the mutation in a larger population. The girl’s relatives, who were unrelated to the first affected family Birk had met, were tested next, along with another 50 Mumbai Jews unrelated to either group.
Birk managed to identify the culprit: the gene SLC38A8. In addition to the two original families, five other unrelated Mumbai Jews also carried the mutation causing the sight problems. But Birk has no idea what SLC38A8 actually does. “The genome project gives you the ABC’s but not what the words mean,” he said. Birk stressed that the disorder is not serious enough for anybody to consider terminating pregnancies over, but said that it does have enough of an impact on quality of life that some families conceiving through in vitro fertilization might consider screening embryos for the mutation.