Practical guidelines to manage discordant situations of <i>SMN2</i> copy number in patients with spinal muscular atrophy
Ivon Cuscó, Sara Bernal, Laura Campello Blasco, Maite Calucho, Laura Alías, Pablo Fuentes‐Prior, Eduardo F. Tizzano
Abstract
Assessment of SMN2 copy number in patients with spinal muscular atrophy (SMA) is essential to establish careful genotype-phenotype correlations and predict disease evolution. This issue is becoming crucial in the present scenario of therapeutic advances with the perspective of SMA neonatal screening and early diagnosis to initiate treatment, as this value is critical to stratify patients for clinical trials and to define those eligible to receive medication. Several technical pitfalls and interindividual variations may account for reported discrepancies in the estimation of SMN2 copy number and establishment of phenotype-genotype correlations.