What are Ashkenazi Jewish Genetic Diseases?
Ashkenazi Jewish genetic diseases are a group of rare disorders that
occur more often in people of Eastern European (Ashkenazi) Jewish heritage than
in the general population. Even though most of these diseases are severe and
life-limiting, some can be treated to reduce symptoms and prolong life. Some of
these diseases can be found during pregnancy through
chorionic villus sampling (CVS) or
amniocentesis. This testing is done usually if one or
both parents are carriers of a genetic disease.
Diseases in this
group include:
- Bloom syndrome. Babies with this
disease are born small and remain shorter than normal as they grow. Their skin
may look red, and they have more lung and ear infections than children normally
have.
- Canavan disease. This disease gradually destroys brain
tissue.
- Cystic fibrosis. This disease causes
very thick mucus in the lungs and problems with digesting
food.
- Familial dysautonomia (FD). People with this problem
cannot feel pain, they sweat a lot, and they have trouble with speech and
coordination.
- Fanconi anemia. People with this
problem do not have enough blood cells and have problems with the heart,
kidneys, arms, or legs. They also are more likely to get
cancer.
- Gaucher disease. This disease causes a
type of fat called glucocerebroside to build up in certain cells of the liver,
spleen, and bone marrow.
- Mucolipidosis IV. This problem causes the nervous system to break down, or
deteriorate, over time.
- Niemann-Pick disease (type A). This disease causes a type of fat called sphingomyelin
to build up in cells of the liver, spleen, lymph nodes, and bone
marrow.
- Tay-Sachs disease. This disease causes
a type of fat called ganglioside to build up in the cells of the brain and
nervous system.
- Torsion dystonia. People with this
problem have ongoing spasms that twist the muscles in their arms, legs, and
sometimes their body. Testing for this condition may not always be done.
Should I have amniocentesis?
Should I have chorionic villus sampling?
Health Tools 
Health Tools help you make wise health decisions or take action to improve your health.
What Is an Ashkenazi Jewish Genetic Panel (AJGP)?
An
Ashkenazi Jewish genetic panel (AJGP) is a blood test that looks for genetic
diseases that occur more often in people of Eastern European (Ashkenazi) Jewish
heritage. These diseases do not just affect people of Ashkenazi Jewish heritage
but are more common in this group of people. Other racial and ethnic groups
have genetic diseases that are more common in their groups.
An
AJGP test tells parents if they have an increased chance of having a child with
certain genetic diseases. Anyone who is interested in knowing his or her
carrier status can ask for the test, but a doctor must
order the test. Different labs may have different tests in the panel.
Talk to your doctor about which diseases are important for your family.
Genetic counseling can help you understand the test
and possible results so you can make the best decision for you.
What Is Carrier Screening?
A
carrier 
is a person who can pass a genetic disease on
to his or her children but does not have the disease. Carrier identification is
a type of genetic test that can help show whether people of high-risk groups
(certain ethnic groups or a family history of a disease) for a specific disease
are likely to pass that disease to their children. This type of test can guide
a couple's decision about having children and making choices about diagnostic
tests during a pregnancy.
An Ashkenazi Jewish genetic panel
(AJGP), done on a blood sample, can see whether you or your partner is a
carrier of genes that cause certain genetic diseases. If positive, the test can
help show whether you and your partner have an increased chance of having a
child born with one of these diseases.
Who Should Be Tested?
Genetic tests can be done for
anyone who wants to know whether he or she is a carrier of certain diseases.
The Ashkenazi Jewish genetic panel (AJGP) shows the chance of having a child
with a disease that is more common among people of Eastern European Jewish
heritage. Anyone who is interested in knowing his or her carrier status can ask
for the test, but a doctor must order it.
Genetic test results
often raise
ethical, religious, or legal concerns. You should have
genetic counseling before making a decision about
testing.
Genetic counselors are trained to explain the test and
its possible results clearly. A genetic counselor can help you make
well-informed decisions.
An AJGP may be recommended for people of
Eastern European Jewish heritage, including:
- Partners of people with diseases on the test
panel. For example, if one partner has
cystic fibrosis (CF) and the other partner has the CF
gene change, a child will have a 50% chance of having CF.
- Couples
planning to have children.
- Pregnant women (and their partners) who
seek prenatal care, whether they have a history of genetic diseases or
not.
- Adults with a positive family history of a disease that is on the
test panel.
What If I Am a Carrier?
It is more common to be a
carrier of a genetic disease, such as
cystic fibrosis (CF), than to have the disease. If
tests show that you are a carrier of a disease, your partner should also be
tested. Both parents must be carriers of a disease for a child to have the
disease.
The tests are not 100% accurate, so a person may test
negative and yet be a carrier. If you are a carrier and your partner tests
negative, there is still a very small chance that you will have a child with
the disease.1
If you and your partner are
both carriers of a genetic disease, there is a 1-in-4 (25%) chance that your
child will have the disease.
- If you are not already pregnant, you may wish
to have
genetic counseling to understand your risks and
options if you decide to have children.
- If you are already
pregnant, you may wish to have tests, such as
amniocentesis or
chorionic villus sampling, to help find out whether
your baby has a disease.
Is the Test Accurate?
About 90% of the time, the
test accurately shows whether or not a person is a carrier of an Ashkenazi
Jewish genetic disease. So, there is a small chance that you may be a carrier
of one of these diseases even if the test results are negative.1
Should I Be Tested?
The decision to be tested is a
personal one. You may wish to be tested if you are concerned that you or your
partner might be a carrier of a disease that is on the test panel. Being a
carrier is more likely if you have a family member with the disease.
Some people decide to be tested to know their chances for having a child
with a disease. For example, among people of Eastern European Jewish heritage,
about 1 in 25 is a carrier of a gene for
cystic fibrosis (CF). The CF gene is less common in
other racial and ethnic groups.
Carrier tests are expensive.
Another factor that may guide the decision to have the tests is whether the
cost of the tests is covered by your insurance company.
You may
decide to have carrier tests if you are already pregnant and the test results
will affect your decision to continue your pregnancy or help you make decisions
about caring for your baby.
Why Not Be Tested?
There may be reasons you would
choose not to have the carrier tests.
- You are already pregnant and the results will
not affect your decision to continue your pregnancy.
- Carrier tests
are expensive. You may decide not to have the tests if your insurance does not
pay for it.
- The tests are not 100% accurate. There is a small
chance that you are a carrier even if the results are normal (false-negative).
Other Places To Get Help
Organizations
| Chicago Center for Jewish Genetic
Disorders |
| Ben Gurion Way, 30 South Wells Street |
| Chicago, IL 60606 |
| United States |
| Phone: | 312-357-4718 |
| E-mail: | jewishgeneticsctr@juf.org |
| Web Address: | www.jewishgeneticscenter.org |
| |
This organization provides public and professional
education about Jewish genetic disorders. It also promotes screening and
prevention programs, information, and referrals. |
|
| Genetic Alliance |
| 4301 Connecticut Avenue NW |
|
Suite 404 |
| Washington, DC 20008-2369 |
| Phone: | 1-800-336-GENE (1-800-336-4363)
(202) 966-5557 |
| Fax: | (202) 966-8553 |
| E-mail: | info@geneticalliance.org |
| Web Address: | www.geneticalliance.org |
| |
The Genetic Alliance is an international organization
made up of millions of people with genetic conditions and more than 600
advocacy, research, and health care organizations that represent their
interests. The Alliance builds partnerships to promote healthy lives for all
those living with genetic conditions. The Genetic Alliance
promotes healthy lives by working to speed the translation of genetic advances
into quality and affordable health care, public awareness, and
consumer-centered public policies. |
|
| Genetics Home Reference, U.S. National Library of
Medicine |
| 8600 Rockville Pike |
| Bethesda, MD 20894 |
| Phone: | 1-888-FIND-NLM (1-888-346-3656) |
| Fax: | (301) 402-1384 |
| TDD: | 1-800-735-2258 |
| E-mail: | custserv@nlm.nih.gov |
| Web Address: | www.ghr.nlm.nih.gov |
| |
The Genetics Home Reference provides information on more
than 250 genetic conditions. It also contains a glossary, a handbook, and other
tools for learning about human genetics and the way genetic changes can cause
disease. The Web site also has links to additional resources for people who
have genetic conditions and for their families. |
|
| Jewish Genetic Disease Consortium |
| 315 West 39th Street |
|
Suite 701 |
| New York, NY 10018 |
| Phone: | 1-866-370-GENE (1-866-370-4363) toll-free |
| E-mail: | info@jewishgeneticdiseases.org |
| Web Address: | www.jewishgeneticdiseases.org |
| |
The Jewish Genetic Disease Consortium (JGDC) is a
collection of smaller, individual organizations that have banded together to
raise awareness of Jewish genetic diseases. The Consortium offers resources to
educate people about carrier screening and how it can help prevent the birth of
children with genetic conditions. |
|
References
Citations
Committee on Genetics, American College of
Obstetricians and Gynecologists (2004). Prenatal and preconceptional carrier
screening for genetic diseases in individuals of Eastern European Jewish
descent. Obstetrics and Gynecology, 104(2):
425-428.
Other Works Consulted
American College of Obstetricians and Gynecologists
Committee on Genetics (2005). Update on carrier screening for cystic fibrosis.
ACOG Committee Opinion No. 325. Obstetrics and Gynecology, 106(6): 1465-1468.
Cunningham FG, et al. (2005). Prenatal diagnosis and
fetal therapy. In Williams Obstetrics, 22nd ed., pp.
313-339. New York: McGraw-Hill.
Credits
| Author | Maria G. Essig, MS, ELS |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Pat Truman, MATC |
| Primary Medical Reviewer | Sarah Marshall, MD - Family Medicine |
| Specialist Medical Reviewer | Siobhan M. Dolan, MD, MPH - Reproductive Genetics |
| Last Updated | April 23, 2008 |
