Each of us has a unique genetic profile that makes us who we are. With every new child, the genetic dice is thrown again as the baby inherits genes from both mother and father—and some new changes that may be thrown in.
Along with your brown eyes and your partner’s dimples, your baby might inherit some genes with genetic misspellings (gene variants) that can cause medical conditions. Most of these gene variants are harmless. Even the ones that can cause harm remain harmless if we carry only one copy. But if your child gets the same variant copy from your partner, he or she may inherit the genetic basis for a serious medical condition.
Today, couples trying to conceive have the tools to identify potential genetic issues before conception. With new genetic tests and genetic counseling, parents now have a better chance of rolling the dice in their child’s favor or preparing for special health needs.
While you’re trying to conceive, schedule a preconception genetic counseling meeting. At the meeting, your doctor will review your and your partner’s family history for birth defects, chromosomal disorders (e.g. Trisomy 21), known inherited disorders, cancer, or family members with mental retardation. A history of two or more pregnancy losses, stillbirth, or infant death may also suggest an underlying genetic cause.
When going through genetic counseling, your doctor may order genetic testing for you and your partner to find out whether you carry genetic variations for some of the most common genetic disorders. Companies including Counsyl and Good Start Genetics offer pre-conception genetic tests through doctors’ offices. Your doctor or genetic counselors can review your genetic blood test results with you to explain your personal risk of passing on troublesome genes to your child.
As part of your genetic counseling, your doctor may ask you about your ethnic background because some genetic variations are more common in some ethnic groups compared to others. For instance, people with Southeast Asian background are more likely to carry the genetic variations for inherited blood disorders such as hemoglobin E. People with European (Caucasian/white) ancestry, are at greater risk of being carriers of the cystic fibrosis gene. If either you or your partner have African (Black) background, you are more likely to carry sickle cell gene variants that cause sickle cell disease. If both you and your partner have any Eastern European Jewish (Ashkenazi Jewish) ancestry, you are at increased risk of passing on a number of genetic diseases including Tay-Sachs disease, Canavan Disease, and familial dysautonomia.
If considering in vitro fertilization (IVF), your doctor may recommend you utilize pre-implantation genetic screening (PGS), a test that is done prior to implantation to screen for embryo chromosome health. To learn more about PGS, read Univfy guest blogger Dr. Ronald Feinberg's article "Gateway to IVF Success:The ABCs of PGS."
If you are already pregnant and have concerns about your family history, then a prenatal genetic counselor can help you determine if it is right for you to have genetic screening for a specific genetic trait or general chromosomal abnormalities. You can choose from a variety of non-invasive prenatal genetic screening tests, as well as more definitive testing through amniocentesis, where a sample of amniotic fluid is drawn from the amniotic sac around the fetus, usually at 16 to 22 weeks of pregnancy, for testing.
If you have specific concerns about your family history, genetic counseling while you’re trying to conceive can help you distinguish conditions that can be passed on through family genetics from those that aren’t inherited genetically. Knowing the odds can help you better prepare for your family’s future.