Options for Carrier Couples
There are a number of options for carrier couples discussed below and in the video A Genetic Counselor on Options:
Carrier couples – where both partners are carriers of Canavan disease, or another similar genetic condition – can build healthy families. But they need to plan carefully, with the help of an informed doctor or genetic counselor, and choose the option that is right for them.
There are a number of options available to a carrier couple that will enable you to have healthy children. We urge any carrier couple to work with a genetic counselor to review their own particular situation and discuss the options in greater detail.
It is best to know your carrier status before starting a family, so you can make informed decisions in a timely fashion.
A carrier couple may choose to become pregnant and test the fetus early in the pregnancy
A couple can become pregnant and test the fetus early in the pregnancy. This can be done by chorionic villus sampling from the placenta (CVS) at approximately 10 weeks, or an amniocentesis (using a sample of amniotic fluid) at approximately 16 weeks. In order to test the fetus, the parents’ carrier status must be known.
There is a 1-in-4 chance for each pregnancy that a carrier couple will have a child affected with Canavan disease. That means that not all pregnancies will result in an affected child—there is a 3-in-4 chance that the child will be healthy.
If the test shows that the fetus is not affected with Canavan disease (or any other serious genetic condition) the parents can continue with the pregnancy.
If the test shows that the fetus is affected by Canavan disease or another serious genetic condition, the parents need to make a decision whether to terminate the pregnancy or continue it, based on their understanding of disease severity, the ultimate impact of the disease on a child and their family, and their resources to deal with a child who can be seriously ill and have a severely shortened lifespan. A genetic counselor can help a couple to make the decision that is right for them.
A carrier couple may choose pre-implantation genetic diagnosis (PGD)
Couples for whom termination of a pregnancy is not an option may want to consider Preimplantation Genetic Diagnosis (PGD). The egg is fertilized outside the body and embryos are tested at a very early stage for the disease carried by the parents. Only embryos with no sign of disease are implanted in the womb.
In many cases, the fetus is screened again at 10 or 16 weeks to be absolutely certain that it is not affected by genetic disease.
A carrier couple may choose to use egg or sperm from a non-carrier donor
The donor should be screened for the disease(s) carried by the man (if a donor egg is to be used) or the woman (if donor sperm is to be used).
A carrier couple may choose to adopt
Adoption is a choice made by some couples who wish to have a family but who choose not to utilize one of the options listed above.
A carrier couple may choose not to have children
Some carrier couples decide not to have children at all.
A carrier may choose not to marry another carrier of the same disease
