Spinal muscular atrophy caused by a novel Alu‐mediated deletion of exons 2a‐5 in SMN1 undetectable with routine genetic testing

摘要

Spinal muscular atrophy (SMA) is an inherited neuromuscular disease affecting 1 in 8,000 newborns. The majority of patients carry bi‐allelic variants in the survival of motor neuron 1 gene ( ). is located in a duplicated region on chromosome 5q13 that contains elements and is predisposed to genomic rearrangements. Due to the genomic complexity of the region and genetic heterogeneity, approximately 50% of SMA patients remain without genetic diagnosis that is a prerequisite for genetic treatments. In this work we describe the diagnostic odyssey of one SMA patient in whom routine diagnostics identified only a maternal heterozygous deletion.