Genetic Screening Tests
Planning on becoming pregnant? Thinking about starting a family? It is important that you be familiar with genetic screening tests to detect carriers of common diseases that should be performed before becoming pregnant. The tests are designed to detect couples at high risk, even with no family history of one or more of the diseases being tested. Genetic screening tests are performed only one time but should be updated before every pregnancy.
Important reminder, the only way to prevent suffering and difficulty involved in delivering an infant with genetic diseases is early diagnosis. The Ministry of Health recommends that every woman planning on becoming pregnant undergo genetic screening. The screening can identify carriers of various diseases but not all genetic diseases.
Note
Note
As of November 15, 2024, a new comprehensive national screening program has been launched in Israel. If you are planning a pregnancy, even if you have been tested in the past, it is recommended that you undergo this new screening. The test is designed for couples, so both partners need to attend. Check with your HMO or the genetic institutes at hospitals to schedule an appointment.
Genetic screening tests can identify carriers of diseases being tested. In the absolute majority of cases, carriers are healthy and are unaware of being carriers. When both biological parents are carriers of the same disease, the offspring face a 25% chance of inheriting this disease. In the case of female carriers of X-chromosome-linked diseases, i.e. diseases in which the disease is found on the X chromosome (such as Fragile X or Duchenne), the offspring is at risk of the disease when only the mother is a carrier.
The difference between prenatal genetic screening tests and screening and diagnostic tests during pregnancy
During pregnancy, the woman should undergo various follow-up tests, including blood tests and ultrasound known as “screening tests”. These tests attempt to determine the level of risk of delivering an infant with Downs Syndrome or other defects, based on a test of the woman and fetus. Other tests that may be performed during pregnancy are diagnostic tests, such as amniocentesis and CVS test, which enable a definite diagnosis of these (and other) diseases in the fetus.
Hereditary (genetic) disease
- A hereditary disease is one that is attributed to a mutation in the genetic material (DNA) that is passed on through hereditary from one generation to the next, from parent to offspring. The screening tests for common and serious hereditary diseases.
- A hereditary disease is considered common if it occurs in more than one out of every 40,000 births, or 1:40,000. This incidence indicates a carrier rate of 1 out of 100.
- A hereditary disease is defined as ‘serious’ if it causes severe morbidity and early mortality.
Genetic screening method
Both partners will be invited to the screening test, where they will receive an explanation, answer questions, complete and sign forms, and where both partners will take a blood test. The testing procedure is gradual, meaning that first the test is performed on the woman's blood sample. If she is found to be a carrier for one of the recessively inherited diseases, her partner will be tested (complete testing for all diseases tested in the screening). If she is found to be a carrier for one of the X-chromosome-linked diseases, the partner does not need to be tested. If her test is normal (no carrier status), the partner will not be tested.
The test can be performed at the expense of the Ministry of Health only once during the period of fertility and is available only to couples. Before performing the test, the site where the test is being performed (HMO or hospital) must make sure that the couple has not already performed the test at another site.
Eligibility for the test and special circumstances
- Eligibility for the test with no partner: When the pregnancy is a single parent pregnancy (either through sperm or egg donation), the test can be performed on one individual only. To obtain eligibility for funding of the test in this case, medical confirmation from a fertility specialist or IVF unit must be presented that confirms the process. Important to know: there is no public financing of a genetic screening test for sperm or egg donors. Furthermore, no test will be performed on anonymous donor sperm for carriers of genetic diseases, as part of the Ministry of Health’s genetic screening.
- Eligibility for test for fertility preservation: women who are about to start a fertility preservation process are not eligible to the genetic screening test at this stage.
- Couples in which only one partner is an Israeli resident: For a couple in which obnly one partner is an Israeli resident (holds a blue ID) and is eligible for health services basket services, both partners may undergo an expanded genetic screening if they plan on living in Israel. To obtain eligibility, the marriage certificate or confirmation of a common-law relationship as well as a declaration confirming their intent to live in Israel must be presented.
Genetic screening test institutes
Genetic screening tests may be performed in HMOs, in genetic institutes in hospitals and in genetic laboratories.
- If the woman and man belong to the same HMO – the screening test may be performed in the HMO’s laboratories.
- If the woman and man belong to different HMOs – the screening test will be performed in the woman’s HMO.
- When performing a genetic screening in a genetic institute in a hospital – no significance for the HMO.
Funding hereditary (genetic) screening tests
Tests for common hereditary diseases (the list of diseases is updated from time to time in accordance with Ministry of Health decisions) is found in the health services basket and are free of charge. The tests can be performed in the HMO or in the genetic institutes of various hospitals.
For your information, a broader genetic screening can be performed through private funding that also include tests for even rarer diseases while somewhat reducing the potential risk of delivering a newborn with one of the diseases being tested.
If both partners are found to be carriers of the same recessive (hidden) hereditary disease
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If both partners are found to be carriers of the same disease, they will face a 25% chance of delivering a baby with the same disease. These couples will be referred to genetic counseling to receive an explanation of the various options available to them.
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If the woman is already pregnant, a diagnostic test will be recommended to examine the condition of the fetus by CVS or amniocentesis. If the fetus is diagnosed with the tested disease, the couple can decide whether to turn to the Pregnancy Termination Board. If the woman is not pregnant, you can also consider performing PGT (Preimplantation Genetic Testing).
If the woman is found to be a carrier of an X-chromosome-linked disease (such as Fragile X and Duchenne)
- These women face a risk of up to 50% of the disease being passed on to the offspring, particularly male offspring.
- These women will be referred to genetic counseling to receive an explanation about the various options available to them.