What are Jewish genetic diseases?
Click here for the Victor Center's matrix to learn more about these diseases and limitations in screening availability and detection rates.
Jewish genetic diseases are a group of disorders that occur with higher frequency in the Jewish population. The Ashkenazi Jews, those whose ancestors were from Central and Eastern Europe (i.e. Poland, Russia, Germany, Lithuania, etc.) are at higher risk than the general population for several genetic diseases. This is primarily due to the fact that the Jewish communities in Europe were small and isolated, and members tended to marry within those communities. Since it is estimated that all individuals carry a small number of gene changes (called mutations), the ones present in those small groups of European Jews became more prevalent in future generations.
What are the diseases?
Below are the Ashkenazi Jewish genetic diseases for which people are most commonly screened. It is estimated that 1 in 4 Ashkenazi Jews is a carrier of a mutation in at least one of these disease genes:
- Bloom syndrome
- Canavan Disease
- Cystic Fibrosis*
- Dihyrolipoamide Dehydrogenase Deficiency (DLD Deficiency)
- Familial Dysautonomia
- Familial Hyperinsulinism
- Fanconi Anemia Type C
- Gaucher Disease
- Glycogen Storage Disease, Type 1a
- Joubert Syndrome
- Maple Syrup Urine Disease
- Mucolipidosis IV (ML4)
- Nemaline Myopathy
- Niemann-Pick Disease Type A
- Spinal Muscular Atrophy*
- Tay-Sachs Disease
- Usher Syndrome Type 1F
- Usher Syndrome Type III
- Walker-Warburg syndrome
*Spinal Muscular Atrophy and Cystic Fibrosis occur at the same frequency in Ashkenazi and non-Ashkenazi Jews.
To learn more about each disease, and their carrier rates, click on the above disease name.
How are the Diseases Inherited?
In each of the cells in our bodies, we have tiny structures called chromosomes. There are thousands of genes on each chromosome. Genes are the basic units of heredity that are passed from parent to child. These genes make up who we are and guide the development of the body. For instance, there are genes for eye and hair color. These genes are in pairs; one is inherited from each parent. Sometimes, a change in a gene, called a mutation, causes the gene to malfunction and can lead to disease.
The diseases mentioned here are inherited in an autosomal recessive manner. This means that males and females are equally likely to be carriers and are equally likely to be affected (have a disease). Individuals who are affected with one of these diseases have two mutations, one in each copy of the gene, for that disease. Carriers have one copy of the gene mutation and one normal working copy of the gene. Carriers are healthy individuals with no signs of the disease, and they are not at risk to develop the disease. If both partners are carriers of a mutation in the same disease gene, there is a 25% chance of having an affected child, a 50% chance of the child being a carrier like themselves, and a 25% chance of the child being neither affected nor a carrier.
