(RNS) — Some 25 years ago, a friend of mine and his wife whose little boy had been diagnosed with Tay-Sachs disease visited our home. A relatively rare genetic disorder that is less so among European-rooted Jews (as well as some French Canadians and Amish), Tay-Sachs allows fatty substances called gangliosides to build up in the brain and spine, causing seizures, vision and hearing loss and paralysis. Victims typically begin to show symptoms at about 3 to 6 months of age. 

It was wrenching to look at the adorable 2-year-old in our living room and realize how short his life would be. And short it was. When my friend called on a rainy night not long after their visit with the sad news that his son had succumbed, I rushed to his apartment. I will never forget the look on the child’s mother’s face when funeral home personnel arrived and the loss hit.

In her recent book, “Fifty-seven Fridays: Losing Our Daughter, Finding Our Way,” Myra Sack recalls her and her husband’s caring for their daughter Havi, who died of Tay-Sachs in 2021 at age 2. Sack explains that some positive things can be gleaned from pain and loss, and tells how the power of community uplifts those who are suffering.

The concept of tragedy as a potential nurturer of blessing is hardly foreign to Judaism or to Jewish history. So it is that since a Haredi rabbi named Yosef Eckstein and his wife lost four children to the disease, Tay-Sachs has become very rare in the Orthodox Jewish community. In 1983, the rabbi saw opportunity to leverage the Orthodox community’s marriage norms to limit, even perhaps eradicate, Tay-Sachs in that relatively insular world.

The gene for Tay-Sachs resides on chromosome 15; if one of two parents carries it, there is no chance their children will contract it. Only if both do is there a chance — 25% — that any child they bear may be afflicted.

Genetic testing for couples before marriage was rare in general at the time, but especially so in the Haredi and the larger Orthodox community, in part because many families imagined they might suffer some stigma if a child tested positive for the defective gene and word got out.

Eckstein’s plan was as inspired as it was ambitious. Since many, if not most, marriages in the Orthodox Jewish world are the result of arranged matches, eligible young men and young women generally meet through a professional matchmaker or through families or friends. If a couple hits it off, other dates follow and, if the young people decide they want to marry, a mazel tov follows.

Eckstein wondered if parents’ reluctance to test could be overcome if the results were anonymized: A random-generated identification number would be assigned to each young person. The only personal information associated with each sample, as a backup identifier, would be his or her date of birth. 

As young people in the community were tested, ideally while still in high school, the results of their blood tests, identified only by number and birth date, would reside in a central database. When two young people wished to meet with marriage as a goal, their ID numbers would be submitted by the respective families. If neither, or only one, of the marriage-minded couple tested positive for the Tay-Sachs gene, they would get a green light.

No report of carrier status would be disclosed. Only if both members of the couple tested positive would they be notified and the planned meeting could be canceled before the young people ever met, sparing them the pain of terminating a relationship that might have already developed.

The program, called “Dor Yeshorim,” Hebrew for “generation of the upright,” a phrase from the 112th Psalm that continues “which shall be blessed.” The nonprofit effort, whose motto is “preventing tears,” is also known as the Committee for Prevention of Jewish Genetic Diseases.

Dor Yeshorim logo. (Courtesy image)

The plural in the name reflects the fact that the program later expanded to include a number of other lethal or severely debilitating genetic disorders that disproportionately affect the Jewish community, such as cystic fibrosis, Niemann–Pick disease and Canavan disease. Those illnesses, like Tay-Sachs, will only manifest if both parents carry the same defective gene.

Disorders arising from dominant gene mutations, where one parent’s defective gene alone can cause the disease, are not tested for by Dor Yeshorim, since such illnesses cannot be prevented by informed mate selection. 

Eckstein was able to convince American and Canadian philanthropists of his idea’s potential and enlisted respected rabbinical authorities to endorse it.

The testing process involves obtaining blood samples and sending them to two separate state-of-the-art labs established for Dor Yeshorim’s purposes. Neither knows the identity of those tested. DNA is extracted from the samples and analyzed. If a test sample shows carrier status, it is automatically retested. “There is,” Eckstein said, “zero acceptable margin of error.”

Hundreds of thousands of individuals have been tested to date. Each year, Dor Yeshorim screens about 20,000 individuals in over 400 schools worldwide for Tay-Sachs and other lethal or incapacitating diseases. 

Thousands of couples have received test results showing their genetic incompatibility. Those couples could still proceed with marriage in mind if they chose, but they were forewarned that their children might be born with the lethal condition. Dor Yeshorim offers professional genetic counseling in such cases. But most who were informed of their genetic incompatibility chose to look elsewhere for marriage prospects.

Dor Yeshorim has also opened offices in Israel and other countries.

The model is workable only in a subgroup that practices arranged marriages. But it can nevertheless be a spur for others at risk for bearing children with genetic diseases to be tested, and thereby prevent heartbreak.

There have been negative reactions in some circles. Some object to the withholding of carrier status from those who test positive but whose potential partners lack the defective gene for a disease. Others have called the charge for the test — several hundred dollars — a “wedding tax.” Others still have accused Eckstein of practicing eugenics, or “playing God.”

No one is coerced to be tested under Dor Yeshorim’s protocols, however, and anyone who wishes can choose to be tested independently. The effort is entirely open about how it operates. And the Orthodox community has largely embraced it wholeheartedly.

In the end, nothing speaks louder than success. Tay–Sachs has become much less common in Orthodox communities. And the Tay-Sachs ward at Kingsbrook Hospital in Crown Heights, Brooklyn, which once had a waiting list of patients, has permanently closed.

(Rabbi Avi Shafran writes widely in Jewish and general media and blogs at rabbishafran.com. The views expressed in this commentary do not necessarily reflect those of Religion News Service.)