SMA SCREENING TESTS

SPINAL MUSCULAR ATROPHY (SMA)

Spinal muscular atrophy (SMA) is a genetically inherited disease characterized by irreversible loss of cranial nerve motor nuclei and anterior horn motor neuron cells in the spinal cord, resulting in muscle atrophy and weakness, that is, muscle wasting. Weakness in the legs is more pronounced than in the arms. In SMA patients, motor nerve cells in the body cannot be fed, and as a result, voluntary muscles become unable to function.

WHAT IS SMA CARRIER SCREENING? HOW IS THE SCAN TEST PERFORMED?

SMA screening is a screening test for early diagnosis of SMA (Spinal Muscular Atrophy), which is a genetic disorder. This test aims to detect the presence of SMA carrier or SMA disease. SMA diagnosis; It is based on examination findings along with history, symptoms and clinical findings. Definitive diagnosis is made by detecting the biallelic pathogenic variant in SMN1 molecular genetic analysis. The blood sample taken from the individual is sent to the genetic laboratory, and a study is started to examine the genetic mutations associated with SMA.
SMA screening may be considered for situations such as premarital, pre-pregnancy counseling, prenatal screening, or in vitro fertilization. This test helps parents find out if they are carriers and potential risks.
Due to the high rates of carriage in our country, SMA carriage should be offered to all couples with or without a sick baby in their family before pregnancy. Once the couple is determined to be carriers, genetic counseling, prenatal or pre-implantation diagnostic testing options may be offered for the healthy child.

WHAT IS THE PURPOSE OF THE SMA CARRIAGE SCREENING TEST?

The aim of the screening is to determine the carrier couples for SMA, to provide genetic counseling to families, to inform and guide them about prenatal diagnosis possibilities, and to reduce the long-term morbidity and mortality of SMA disease. The genetic test to be performed is to determine the possible carrier status of SMA (Spinal Muscular Atrophy) disease and does not cover the diagnosis or carrier of other genetic diseases. With the result, another genetic examination may be required or the analysis may need to be repeated. It is recommended that a couple planning pregnancy wait for the screening test results.

HOW LONG WILL THE SMA CARRIAGE SCREEN RESULTS BE DEFINED?

SMA (Spinal Muscular Atrophy) screening results can vary depending on the type of test performed and which lab is performing the analysis. The time it takes for results to come back may vary depending on the complexity of the genetic test and the laboratory's workload. However, results are usually available within a few weeks. It is important to contact a geneticist or healthcare professional for clarity and interpretation of the results. It is also critical to receive accurate information about how to interpret the results and what precautions should be taken.

HOW DOES THE PROCESS WORK IF THE SMA CARRIAGE SCAN IS POSITIVE?

SMA; It is an inherited, progressive lower motor neuron disease. On average, one in every 50 individuals in the society is a carrier for SMA disease. In a situation where both father and mother carry the disease, the risk of developing the disease in each baby to be born is 25%. SMA disease is a chronic disease, despite treatments that alter its natural course. These treatments also require regular check-ups and care. Therefore, if both spouses/couple candidates are carriers, the couples are informed about the disease and possible consequences of the disease, and they are directed to receive genetic counseling from a Medical Geneticist for further diagnostic examinations of the disease.

Couples who are carriers of SMA worry about conceiving naturally, as they run the risk of passing this genetic disease on to their children. In vitro fertilization (IVF - In Vitro Fertilization) treatment provides a solution for these couples to select healthy embryos through genetic tests and screenings and transfer them to the womb of the expectant mother.

If the SMA Screening Test Result Is Positive, The Following Steps Are Followed;

1. Genetic Counseling: The first step should be to meet with a genetic counselor. Couples are directed to seek genetic counseling from a Medical Geneticist to assess their carrier status and risks.
2. In vitro fertilization (IVF - In Vitro Fertilization) Treatment: In vitro fertilization treatment begins to select healthy embryos. During this process, the woman's eggs are collected and fertilized in the laboratory with sperm taken from the man.
3. Genetic Tests: The resulting embryos are subjected to genetic tests. These tests performed on embryos enable it to be determined whether they are SMA carriers.
4. Selection of Healthy Embryos: After detecting healthy embryos in terms of SMA Carrier, they are transferred to the uterus of the expectant mother.
All patients who apply as Istanbul IVF Center are informed about the SMA carrier screening test. Our patients who want to be scanned must first fill out a consent form.

After the blood samples taken from individuals for SMA screening in our center, the result of the genetic screening is shared with our couple. "We are delighted to lead couples wishing to have children on SMA disease awareness."
Page content is for informational purposes only. The page content does not include elements related to therapeutic health services. Be sure to consult your doctor for diagnosis and treatment.

Edited on September 6, 2023
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