Common Genetic Diseases in the Ashkenazi Jewish Population
By S. Norek
Several recessive genetic diseases are more likely to be found in Ashkenazi Jews and Jewish individuals with Eastern European blood than in other populations. However, genetic testing and counseling can identify individuals at risk for having children with these diseases and informed decisions can be made. The most common recessive genetic diseases found in this category are Niemann-Pick, Canavan, Gaucher, and Tay-Sachs.
Each one of these diseases is devastating, and usually, deadly. The first, Niemann-Pick disease manifests itself in several forms, but Types A and B Niemann-Pick disease are the ones more often seen in Ashkenazis. Children with Niemann-Pick suffer from crippling neurological disintegration that will end their lives well before their teens. About one in a thousand Jews of Ashkenazi descent carry the genetic mutation that can result in Niemann-Pick diseases.
Canavan disease is caused by an enzyme deficiency. One in forty Ashkenazis carry the genetic mutation that causes Canavan. As with Niemann-Pick, children with Canavan are inflicted with the gradual deterioration of their nervous systems and do not usually reach the age of five.
Although severely debilitating, Gaucher disease is not often deadly. Individuals with Gaucher suffer from metabolic errors that cause joint problems. These problems include frequent breakage and a thinning of the bones, similar to that found in osteoporosis. One in ten Jews of Eastern European descent carry the genetic mutation causing Gaucher Disease.
Tay-Sachs, the most widely known genetic disease more particular to the Ashkenazi Jewish population, is manifested by the gradual collapse of the central nervous system. Children with Tay-Sachs do not customarily reach the age of five. The genetic mutation for Tay-Sachs disease is ten times more frequently found in the Ashkenazi Jewish population than in other populations.
Individuals with the genetic mutation in their DNA that causes one of the aforementioned illnesses are known as carriers. Although carriers do not actually have the disease associated with the particular genetic mutation, when two carriers with the same mutation have children, the children are at increased risk for having the disease in question. In particular, if both parents are carriers, they have a one in four chance of bearing a child with the disease. The illness will be caused by the inheritance of two genetic mutations, one from each parent. In addition, there is a one in two chance that a child will also be a carrier.
If you are thinking of having children, please get tested. A simple blood test can determine whether or not you carry the genetic mutations for the mentioned diseases and many others. A listing of certified laboratories throughout the world can be found at www.ntsad.org/ntsad/.