In the year 2010, Israel had a total of two cases of Tay-Sachs disease, in a pair of twins. The fatal genetic disorder was detected in just one child in 2005, and in one other in 2004, says Joel Zlotogora, director of the Department of Community Genetics at the Israel Ministry of Health.
- Maybe the real question is why marry at all?
- Maybe the real question is why marry at all?
- Word of the Day / Hatan: Looking like a lawyer at your wedding
- Scientists discover gene that predisposes Ashkenazi Jews to schizophrenia
- Can BPA make you fat?
- Studying Talmud in the morning, writing code in the afternoon
- Neanderthals had sex with other species - and family, DNA study shows
Tay-Sachs, which was once prevalent among Ashkenazi Jews of Eastern European origin, has been almost eradicated in Israel. In the United States, its incidence has dropped from 100 cases a year to around ten—and most of those cases are now diagnosed among non-Jews.
How has the disease's near-extinction been achieved? Through a combination of prenatal testing and pregnancy termination – and mainly, among the ultra-Orthodox community in both Israel and in the U.S., due to premarital genetic testing. In fact such testing has become not just a normal part of the matchmaking process: it is often a make-or-break prerequisite for a shidduch, or arranged marriage.
Before proceeding with a proposed shidduch, the Haredi couple first undergoes testing for mutations that cause Tay-Sachs and other genetic diseases common among Ashkenazi Jews. Couples whose tests reveal that they both carry the same mutation for a specific disease – meaning their children have a one-in-four-chance of being sick - do not meet again.
Not that that is likely to cause much heartbreak. According to Israel Rosman, who works as a patient advocate for Orthodox Jews at New York University’s Langone Medical Center in New York City, most Haredi couples meet two or at most three times before deciding to marry.
Taking the trend a step further, many ultra-Orthodox are preemptively tested in their teens, at high-school age, well before any shidduch is on the agenda, says Rosman, who was tested prior to his own arranged marriage.
Although a very small minority of Ultra-Orthodox rabbinical families object to testing—on the grounds that whatever happens is the will of God—the overwhelming majority of Haredim “feel that this is a very important thing,” Rosman says. “I was very happy when I did it; it gave me peace of mind.”
N237y2 and 83e2 fall in love
In Israel and in the U.S., the primary organization testing the Ultra-Orthodox community is Dor Yeshorim (“Upright Generation”) also known as the Committee for Prevention of Jewish Genetic Diseases.
Dor Yeshorim was founded in New York in 1983 by Rabbi Josef Ekstein, a Satmar Hassid of Hungarian origin who saw four of his children die from Tay-Sachs, which causes catastrophic nerve damage starting in the womb, leading to paralysis and death typically by age four or five.
Since its inception Dor Yeshorim has informed some 2,000 couples that they are incompatible because they both carry the same mutation for a specific disease.
“We told them, ‘don’t continue with the shidduch,’” says a representative of the Jerusalem office who refused to give her name. “They don’t close a shidduch without Dor Yeshorim.”
The panel of diseases for which Dor Yeshorim tests include Familial Dysautonomia, which disrupts the nervous system, causing insensitivity to pain, difficulty swallowing and speaking, and extreme blood pressure swings; Canavan Disease, a developmental disorder that strikes nerve cells in the brain; and Bloom Syndrome, which results in short stature, an increased risk of cancer, and infertility in men.
Genetic mutations for all of these diseases are recessive, meaning that a person has to carry two copies of the faulty gene—one inherited from each parent—in order to show symptoms.
Yet those tested by Dor Yeshorim never learn if they carry a mutation. Instead, each person is given a number; when they meet a potential partner, both feed their numbers into the Dor Yeshorim system. If both the man and the woman are found to carry a recessive gene for, say, Tay-Sachs, the organization informs them that they are not a match. “You’ll call up the office and say, “Is 123 a match with 12378? And if they say ‘yes,’ you’ll break the plate: the engagement is done,” Rosman says.
The downside of testing teenagers
That model doesn't work for everyone, says Karen Litwack, executive director of the Center for Jewish Genetics in Chicago, which tests for 19 Jewish genetic disorders - and gives people their results.
“The two problems with Dor Yeshorim is that people are not told which genes they are carrying,” says Felicia Axelrod, the world’s foremost expert on Familial Dysautonomia. Axelrod, a professor of pediatrics and neurology at NYU Langone Medical Center, has watched the rare disease decline from 15 to 20 cases per year in the 1990s to just five new cases globally in 2009, thanks to the discovery of the FD gene in 2001.
The other problem is that Dor Yeshorim tests people at a young age. But people don't keep up with new discoveries in genetics, and if tested in their teens more than a decade ago, they may not come back for updated testing. "Some of the children whom I see with Familial Dysautonomia are born to parents who were tested prior to the discovery of the gene in 2001,” Axelrod says.
Nevertheless, she believes that the work of Dor Yeshorim is “very very important, because they are probably our only or one of the best avenues into the Orthodox community regarding testing and increasing awareness. Their reach is extensive and that is a tremendous plus.” And what is more, she says, “They did it when nobody else was. And we have to appreciate that.”