genetic carrier screening for spinal muscular atrophy results You Can trust

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1 genetic carrier screening for spinal muscular atrophy results You Can trust

2 Spinal Muscular Atrophy (SMA) Carrier screening What Is SMA Carrier screening? Carrier screening tests help identify individuals who may have an increased risk of having a child with certain genetic conditions. Some parents want to know whether they have a higher chance to have a child affected with a genetic condition like SMA. Results of carrier screening can help you make informed reproductive decisions, such as whether to consider follow-up prenatal diagnostic testing. You may want to have SMA carrier screening if: You have a family history of SMA Both parents are known carriers of SMA Ultrasound findings indicate an increased risk for SMA You are interested in knowing what your risk is to have a child with SMA even without a known personal or family history reason/indication

3 What Is SMA? SMA (spinal muscular atrophy) is a severe, often fatal, genetic disorder in which muscles involved in many essential functions, such as breathing, eating, and movement, become progressively weaker and ultimately waste away (atrophy). About one in every 6,000 10,000 babies is born with SMA and is the most common recessive disease after cystic fibrosis. 1 How Is SMA Inherited? SMA is inherited in an autosomal recessive pattern. This means that, in order to be affected, a person must inherit two disease-causing mutations - one from each parent. To be at-risk to have an affected child, both parents must be carriers of the mutated SMN1 gene. 2 If both parents are carriers, there is a one in four (25%) chance with each pregnancy that a child will have SMA, and a one in two (50%) chance that a child will be a SMA carrier. Father Gene Mutation) Mother Gene Mutation) 25% 50% 25% (Uaffected and not a carrier of gene mutation) gene mutation) gene mutation) (Affected) Normal Gene Gene Mutation spinal muscular atrophy Inheritance

4 What Causes SMA? SMA is caused by a mutation (change) in a gene (a DNA sequence on a chromosome) called SMN1 (Survival Motor Neuron) located on chromosome 5. This gene makes a protein that is thought to have an important role in the functioning of motor neurons in the spinal cord. Three Types Of SMA Type I: The most common form, type I, affects about 70% of patients and is the most severe. ren with type 1 SMA usually die from respiratory failure before the age of two. In fact, SMA is the leading genetic cause of death in early childhood. 1 Type II: ren with type II SMA may be able to sit unaided, but cannot stand or walk unaided. These children typically do not live past age four. 1 Type III: Although they face many challenges, children with type III SMA are not able to walk unaided or have a normal lifespan. 1 The SMA Carrier Screen The SMA Carrier Screen test is a simple blood test that can determine if you or your partner is a carrier of a mutation causing SMA. Results are typically available to your health care provider within two weeks. Quality answers about familial risk Appropriate follow-up testing if risks are discovered.

5 + What Does a Positive Carrier Screen Test Result Mean? A positive SMA carrier screening test result means you have one copy of a mutation that is known to cause SMA. It does not mean you have SMA. If you are found to be a SMA carrier, then your partner should consider testing. If you are both found to be SMA carriers, your health care provider will discuss reproductive and prenatal testing options with you. - What Does a Negative Carrier Screen Test Result Mean? A negative SMA carrier screening test result significantly reduces your risk to be a SMA carrier, but it does not reduce your risk to zero. For more information, ask your health care provider or visit sequenom.com/laboratories

6 no test is perfect. While results of this testing are highly accurate, a negative test result does not eliminate the chance of being a carrier. the results of this testing, including the benefi ts and limitations, should be discussed with your health care provider. Sequenom laboratories, a wholly-owned subsidiary of Sequenom, inc., is a cap-accredited and clia-certifi ed molecular diagnostics laboratory dedicated to improving patient outcomes by offering revolutionary laboratorydeveloped tests for a variety of prenatal and eye conditions. Sequenom laboratories pioneered nipt for fetal aneuploidies with the launch of its Maternit21 plus test, and offers a full menu of prenatal tests. the heredit Spinal Muscular atrophy carrier Screen test is a laboratory-developed test that was developed, validated and is performed exclusively by Quest laboratories under contract with Mt. Sinai genetic testing laboratory, and is available through contract with Sequenom laboratories. references 1. acog committee opinion no update on carrier screening for cystic fi brosis. american college of obstetricians and gynecologists. Obstet Gynecol. 2011;117(4): prior tw. acmg practice guidelines. carriers screening for Spinal Muscular atrophy. american college of Medical genetics. Genet Med. 2008;10(11): Sequenom laboratories 3595 John hopkins court San Diego, ca info@sequenom.com sequenom.com/laboratories toll Free (within the us) at Sequenom and heredit are trademarks of Sequenom, inc. and used with permission by Sequenom center for Molecular Medicine, llc, dba Sequenom laboratories Sequenom laboratories. all rights reserved r