Community Magazine June 2009

54 COMMUNITY MAGAZINE Misconceptions and Misunderstandings The complex nature of genetics has given rise to considerable misunderstanding regarding genetic diseases, particularly with respect to recessive disorders. Unfortunately, carrying a genetic disorder is often mistaken for suffering from a genetic disorder. Those unacquainted with genetic science find it difficult to imagine how a person with a genetic defect can be totally healthy, or how this defect has no possibility of affecting his children. But this is, in fact, the way genetics work. If a carrier of a recessive gene marries a non-carrier, then their children – each and every one of them – have no chance of inheriting the disorder. And even if both parents are carriers, as we saw, each child has a 75 percent chance of not suffering from the disorder, and a 25 percent of not even carrying the mutation at all. This can usually be determined through a simple blood test. Unfortunately, all this can sometimes cause unnecessary anxiety and angst in the context of matchmaking. Young men and women, and their parents, often, as a matter of inviolable policy, keep away from prospective matches who have been determined to be carriers of a genetic disorder. Sadly, the fallacy underlying this knee-jerk tendency is often lost on singles, parents and matchmakers. Once a person is determined not to be a carrier of a recessive disorder such as Tay-Sachs – even though it may have run in his/her family – he/she has absolutely no possibility of passing that disease on to the next generation, regardless of whom he/she marries. In fact, even if he/she marries somebody whose siblings died from the recessive disorder, Heaven forbid, the children of this union have no chance of becoming sick from the disease. As such, experts widely condemn – both scientifically and ethically – stigmatizing carriers or family members of sufferers, to disqualify them for marriage eligibility. Dor Yeshorim A creative solution for this problem was implemented in 1983, with the founding of Dor Yeshorim, or the Committee for Prevention of Genetic Diseases, which launched and continues to run a massive screening campaign for common Ashkenazic disorders. Its founder, Rabbi Yosef Ekstein, lost four children to the devastating Tay-Sachs disease between the years 1965-1983. His organization seeks to eliminate this and other genetic diseases from the Ashkenazic population through large-scale, premarital screening. The method employed by Dor Yeshorim is simple, yet brilliantly designed to ensure complete anonymity and avoid misguided stig- matization. Jewish youngsters are tested well before they contem- plate marriage, usually during their high school years, but are not told the results. Instead, they receive a personal identification num- ber which they keep until they are ready for marriage. At that point, the prospective marriage partners contact the Dor Yeshorim offices and submit their PIN numbers; they provide no other information, certainly not their names. The Dor Yeshorim operator – who, as an additional safeguard against disclosure, identifies himself/herself 1) GSD III (Glycogen Storage Disease, Type III; also known as Cori’s Disease, or Forbes Disease) GSD III hampers the body’s ability to process glycogen, the “fuel reserve” where the body goes for energy when a person has not eaten or engages in strenuous activity. Patients suffer- ing from this disorder will experience low blood sugar with fast- ing, liver enlargement, and, in some cases, muscle weakness. GSD III is found most commonly among Jews of North African descent (Moroccans, Algerians, Tunisians, etc). 2) G6PD (Glucose-6-Phosphate Dehydrogenase Deficiency) Patients with low levels of G6PD in their red blood cells can suffer anemia of varying degrees of severity. Often, the ane- mia is triggered by certain drugs or infections. It surfaces most commonly in populations with origins in Africa, the Middle East, and some Mediterranean countries. G6PD differs from the other Sephardic genetic disorders in that with current technology, car- rier status cannot be determined through screening. 3) Beta-thalassemia This disorder affects the supply of hemoglobin, the substance in the blood that carries oxygen to the body tissue. Like G6PD, Beta-thalassemia can cause varying forms of anemia. It occurs mainly in people of Mediterranean descent, particularly those originating from Greece or Italy. 4) FMF (Familial Mediterranean Fever) FMF, the most common of the Sephardic genetic disorders, causes occasional bouts of fever, abdominal pain, lung inflam- mation and arthritis. It occurs most frequently among North African and Iraqi Jews. Unlike other Sephardic genetic diseas- es, FMF has a high frequency among Ashekenazim, as well, though generally in a much milder form. 5) MJD (Machado Joseph Disease) By far the most devastating of the Sephardic disor- ders, MJD attacks the nervous system during early- to mid-adulthood, much like Lou Gehrig disease, leaving the patient crippled and paralyzed, and ulti- mately resulting in death. It occurs primarily among those of Portuguese and Azorean descent, and the defective gene is believed to have arrived in North America in 1845. Most of the information here is taken from the Jewish Genetics Center in Chicago www. jewishgeneticscenter.org Sephardic Genetic Diseases and Azorean descent, and the e is believed to have arrived in North