Health Ministry said to flag error in genetic test kit detecting rare mutation, reread results

Haaretz report concerns MECR mutation, part of Israel’s expanded screening panel; can lead to problems with movement, speech, vision; rare disease more common among Ashkenazi Jews

The Health Ministry’s discovery of a malfunction in test kits used to detect a genetic mutation especially common among Ashkenazi Jews has reportedly led to the formation of a special review committee.

The test looks for a mutation in the MECR gene that increases the risk of a severe genetic neurological disease in fetuses. The genetic screening tests were produced by the company Thermo Fisher and used for pregnant women or those planning a pregnancy, and for biological fathers, according to a report in Haaretz.

The ministry’s announcement came after Sheba Medical Center reported a case in which a woman had been tested at her health network with a screening kit from the company Gamidor and had been told she was a carrier.

Later, she chose to undergo an expanded screening test at Sheba, which used the Thermo Fisher kit. The second result erroneously indicated that she was not a carrier, Haaretz reported.

An investigation revealed that the error came from a computer malfunction in the software used to analyze the laboratory samples.

Following the discovery, the publication said that the ministry instructed all genetic laboratories that used the faulty software to reread the tests. Since then, the ministry stated that the malfunction had been corrected and that laboratories were completing new readings of the results.

More than 95 percent of the tests were reread, revealing 109 new carriers.

Among the carriers was one couple in which both partners were carriers, a situation that creates a higher risk of disease in offspring, Haaretz said. The woman, however, was not pregnant, so no fetal testing or pregnancy termination was required.

The investigation also found a problem in detecting another mutation in the same gene. The ministry ordered genetic laboratories to conduct further checks for individuals at high risk without requiring a new blood sample.

The MECR mutation

The MECR mutation is one of many included in Israel’s expanded genetic screening panel. The mutation can lead to problems with movement, speech, and vision in children, but it usually does not affect their cognitive abilities. The disease is rare but more common among people of Ashkenazi Jewish origin.

To reduce the risk of having children with severe genetic illnesses, Israel encourages couples to undergo screening.

The program has been offered in the public health system since 2008 and, over time, has expanded to include hundreds of diseases and mutations. The goal is to help couples understand their reproductive risks and make informed decisions.

Tracing Ashkenazi Jews back to 350 individuals

According to research, all Ashkenazi Jews can trace their ancestry to a “bottleneck” of just 350 individuals, dating back to between 600 and 800 years ago.

Because the Ashkenazi community originated from a small population and remained genetically isolated, it developed a higher load of disease-causing mutations. Ashkenazi Jews are still known to be at higher risk for many diseases, including breast and ovarian cancer and Tay-Sachs disease.

Many potentially disease-causing mutations in Ashkenazi Jews remain unknown.