Preventing Jewish genetic diseases

GILLIAN KLAWANSKY

“There’s the heartwrenching story of a couple who left genetic screening really late in their relationship and were in total denial about what the consequences would be,” says Rabbi Chaikin, Dor Yeshorim’s South African representative.

“They went through real pain when they discovered they were both carriers of genetic diseases – I referred them to genetic counsellors and doctors and they each went to see their own doctors. They ultimately made the decision not to get married and I had to counsel the families on both sides. It really took everything out of me.” Sadly, leaving genetic screening late, is too often the cause of such turmoil.

Under the auspices of Dor Yeshorim, Rabbi Chaikin therefore actively encourages young Jewish people to test as early as possible to see if they’re carriers of Ashkenazi genetic diseases. In so doing, the non-profit is working to prevent the incidence of children being born with these severe and often fatal conditions.

A genetic carrier is a person who has inherited a recessive genetic mutation but has no symptoms of the disease themselves. If only one spouse is a carrier, there’s no chance of their children being affected.

“However, if two carriers marry one another, the chances of their children being affected are 25 per cent,” explains Rabbi Chaikin.

Promoting early, premarital testing to avoid such a scenario, Dor Yeshorim teamed up with Hatzolah last Sunday to facilitate their annual mass screening. With Hatzolah’s support, Dor Yeshorim runs this annual campaign offering mass screenings for these Jewish genetic diseases at subsidised rates.

At Sunday’s screening, 40 people were tested at Hatzolah’s headquarters.

While most people are tested at these annual events, screening through Dor Yeshorim is offered throughout the year with an average of 25 people taking advantage. The screening process involves drawing blood, explains the rabbi.

The blood is then sent to the lab for processing, where DNA is extracted and genes can be read. Results from school and mass screenings take three to four months, although results can be fast-tracked.

Dor Yeshorim oversees this anonymous process where those tested provide their birth date and gender and are then given a number entered onto Dor Yeshorim’s database.

In South Africa, Dor Yeshorim suggests that people as young as 18 get screened. “Their philosophy is to avoid carriers marrying one another, by screening very early on and suggesting to those who aren’t genetically compatible to not even date, and certainly not to get engaged or get married.

“Before a couple allows anything to get serious or even starts dating, Dor Yeshorim cross checks the numbers in the database to ensure they aren’t both carriers. “It works very well in a shidduch environment,” explains Rabbi Chaikin.

People tested through Dor Yeshorim never receive their results, as research suggests it’s better not to know. Results are only revealed to them if they meet someone who is also a carrier.

“If you get a couple who are both carriers, it requires some genetic counselling and advice and sometimes halachic advice, as they’ll want to ask their rabbi if what the doctor says is correct,” says Rabbi Chaikin.

“Dor Yeshorim has an international call centre where people are referred to someone for support – in South Africa couples are generally referred to me.”

For those wanting to know their results, it’s recommended they do the tests directly through Lancet Laboratories or speak to their doctors for advice. 

The Jewish genetic diseases 

While many of us are familiar with Tay-Sachs, there are nine debilitating genetic diseases that a basic screening panel covers. These are:

• Tay-Sachs, Canavan Disease and Niemann-Pick Type A, which are all a fatal metabolic dysfunction that results from the body’s inability to break down certain substances – sick children rarely reach the age of five. According to its website, Dor Yeshorim is credited with singlehandedly eradicating Tay Sachs from the Jewish community.

  Studies suggest that Canavan Disease affects one in 6 400 to 13 500 people in the Ashkenazi Jewish population. The incidence of Niemann-Pick within the Ashkenazi population is approximately one in 40 000 individuals.

• Cystic fibrosis, which manifests itself in serious respiratory ailments as well as other health problems of varying severity. Approximately 1 000 new cases are diagnosed annually in the general population.
• Familial Dysautonomia, which mainly affects the central nervous system that is responsible for many of the body’s systems, such as blood pressure stabilisation, motor function, and the sensory nervous system. This disease affects about one in 3 700 individuals in Ashkenazi Jewish populations. 
• Fanconi Anaemia Type C, which manifests itself in severe anaemia, congenital defects in the extremities and a tendency towards cancer and leukaemia. This occurs in one in 160 000 individuals worldwide.
• Glycogen Storage Type 1A where patients lack the ability to break down sugar, which frequently leads to liver tumours and can be fatal.
• Bloom Syndrome, typified by dwarfism, a tendency towards malignant tumours, chromosomal instability, sometimes mental retardation and more. Only a few hundred affected individuals have been described in medical literature. However, about a third of these are of Central and Eastern European (Ashkenazi) Jewish background.
• Mucolipidosis Type 4, a severe degenerative disease of the brain that hampers neurological and motor development and causes blindness. Some patients reach adulthood, but never develop beyond the level of a 12-18-month-old. This disease is estimated to occur in one in 40 000 people. About 70 per cent of affected individuals have Ashkenazi Jewish ancestry. 

“Tests have recently been devised for another seven conditions. One can test for those as an optional additional panel which is likely to become standard as well in the near future,” explains Rabbi Chaikin. 

To find out more, visit: http://doryeshorim.org or contact: Rabbi Yossi Chaikin on 083-794-1178.