Heterozygote screening techniques are almost equally effective in SMA

Chinese researchers tested five different laboratory techniques designed to determine the status of the SMN1 and SMN2 genes in 516 reference samples.

  • These techniques included: MLPA, quantitative PCR (qPCR), digital microdroplet PCR (ddPCR), high-resolution analysis (HRM) and capillary electrophoresis PCR (CE PCR);
  • MLPA remains the reference method, but requires considerable laboratory time and resources,
  • the other four techniques have sensitivities and specificities very close to MLPA,
  • They can, however, determine the presence of a SMN1 gene deletion, usually at a lower cost, and provide a great deal of information on the SMN2 gene copy number.

However, these techniques have their limitations, as they do not detect subjects with a 2-0 SMN1 genotype. This comparison will be very useful for decision-makers in the context of neonatal screening and/or screening for SMA heterozygotes in the general population.

 

Evaluating the performance of four assays for carrier screening of spinal muscular atrophy. Tan J, Zhang J, Sun R et al. Clin Chim Acta. 2023 Juil.