Thomas J. Dimino, M.D. M. Victoria Lopez-Beecham,M.D Luis P. Leyva Jr., M.D.
Ilya S. Johnson, M.D. Manal S. Antoun, M.D. Ana R. Hernandez, M.D.
Paola A. Bordoni, M.D. Anna T. Davis, M.D.
Informed Consent/Decline for SMA Carrier Screening
1. What is Spinal muscular atrophy? SMA is a hereditary disease that destroys the nerves responsible for controlling voluntary muscle movement, but does not affect intelligence. Muscles that control breathing, swallowing, head and neck control, walking and crawling are the most severely affected. SMA is a variable disease in terms of when the symptoms begin. Most often it shows up before a baby is two years old, but in some individuals the symptoms start before birth and in others not until after age 30. There is currently no
2.How is SMA inherited? If both parents are carriers of an abnormal SMA gene, there is a chance that each parent will pass the abnormal gene on to their child. An individual with two abnormal SMA genes will be
affected with the disease. With each pregnancy there's a:
25% (1 out of 4) chance that the child will inherit two normal SMA genes, and will be neither a
carrier nor affected with the disease
50% (2 out of 4) chance that the child will inherit one normal and one abnormal SMA gene, and will be a carrier of SMA (but not affected) 25% (1 out of 4) chance that the child will inherit two abnormal SMA genes - one from each parent
- and will be affected with the disease.
3.What is the purpose of SMA carrier screening? The purpose of SMA carrier screening is to see if O coupleis
at increased risk for giving birth to a child who will be affected with SMA. The test is done on a sample of blood. If results show that a couple is at high risk, prenatal testing (chorionic villi sampling [CVS] or amniocentesis) during pregnancy or preimplantation testing before pregnancy can be done to see whether or not the baby has inherited two abnormal SMA genes. Neither carrier screening nor prenatal diagnostic testing can tell what type of SMA the child could have.
4.If my test is negative, could I still be a carrier? A negative result significantly lowers, but does not completely
eliminate the risk of being a carrier of SMA. Carrie screening does not detect les common abnormalities (mutations) that cause SMA.
5.Is there a cost for this test? This is a routine clinical laboratory test and the results may aid in your diagnosis;
thus, you or your health insurer will be billed for this procedure.
The decision to consent to or to refuse SMA testing is entirely mine.