Spinal Muscular Atrophy Carrier Screening, Deletion/Duplication Analysis, Varies

Casandra

Casandra Test Code MC78006Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID SMNCSCPT Codes 81329, 88233, 88240

Spinal Muscular Atrophy Carrier Screening, Deletion/Duplication Analysis, Varies

Clinical Use

Use

This test is useful for carrier screening for spinal muscular atrophy (SMA) in the general population and for reproductive partners of known SMA carriers. It is also useful for carrier screening for parents of a child with a known deletion of the SMN1 gene or other family history of SMA. SMA is an autosomal recessive disorder characterized by motor neuron degeneration, muscular atrophy, and paralysis. The severity of SMA is associated with the number of copies of the SMN2 gene present, with more copies associated with a milder phenotype.

Special Instructions

A previous hematopoietic stem cell transplant from an allogenic donor will interfere with the testing results. Informed consent is required for New York clients. The test should be performed before conception or early in pregnancy, as recommended by the ACMG and ACOG.

Limitations

Point mutations are undetectable by this assay and it cannot definitively discriminate between two copies of SMN1 on the same chromosome versus on separate chromosomes. Rare polymorphisms could lead to false-negative or false-positive results. If results do not match clinical findings, additional testing should be considered. Interpretation may be affected by improper specimen collection, handling, or test selection.

Test Details

New York Approved