Should I Get Genetic Carrier Screening?
If both parents are carriers, there is a 25% chance that the child will get the abnormal gene from each parent and will have the disorder. There is a 50% chance that the child will be a carrier of the disorder—just like the carrier parent. There is a 25% chance that the child will only inherit the normal genes. If only one parent is a carrier, there is a 50% chance that the child will be a carrier of the disorder and a 0% chance that the child will have the disorder.
Preimplantation Genetic Testing – Mutation (PGT-M) can be performed to test the embryo of a couple who are both carriers of the same disease. This allows us to identify which embryos would result in a child born with the disorder. We can also identify the healthy embryos without the disease to put back in a woman’s uterus for her to have a child without the disease. More on PGT-M below.
Ethnic groups with an increased risk of genetic disorders include:
- Non-Hispanic white individuals should be offered cystic fibrosis carrier screening.
- People of Eastern European Jewish descent (Ashkenazi Jews) should be offered screening for Tay–Sachs disease, Canavan disease, familial dysautonomia, and cystic fibrosis. Individuals can ask about screening for other disorders. Carrier screening is available for mucolipidosis IV, Niemann–Pick disease type A, Fanconi anemia group C, Bloom syndrome, and Gaucher disease.
- People of African, Mediterranean, and Southeast Asian heritage should be offered screening for thalassemias and sickle cell disease.
Though targeted genetic screening can be performed, many resources, such as NxGen, now offer carrier screening for up to 120 genetic disorders that can affect your pregnancy, the health of your baby, and your family’s future in one simple test. These tests can be viewed as a way to provide a couple with the most information before they start treatment or add to their family.
In addition to the genetic screening, patients will receive genetic counseling to discuss the results. If a patient and partner learn that they are both carriers of a genetic mutation, there are several options:
- They can proceed with becoming pregnant, then undergo prenatal diagnosis with amniocentesis or chorionic villus sampling to see if the baby is affected.
- They could also undergo in vitro fertilization with preimplantation genetic testing – mutation (M) to identify the affected embryos and avoid using those to become pregnant. NxGen will assist with the costs of such treatment in the event a couple is identified as being carriers of the same mutation.
- Couples also have the option of using donor sperm or donor eggs that do not have the mutation so that their child will not be affected.