SMA carrier testing: a meta-analysis of differences in test performance by ethnic group

Spinal muscular atrophy (SMA) is a severe autosomal recessive genetic disease that occurs in about one in every 10 000 births. Prenatal carrier testing is available for SMA, and the utility of universal screening is actively debated.

The aim of this study was to perform a systematic review and meta-analysis of SMA genotype frequency, carrier frequency, and carrier test performance in different ethnic groups.

We performed a systematic review of the literature for studies on SMA carrier screening test performance. Ethnicity-specific allele frequencies, carrier rates, and screening test performance were determined from data of 169 000 individuals in 14 published studies. Pooled estimates were calculated for each ethnic group using a random effects meta-analysis.

The detection rate of SMA screening in the non-Black population was 87-95%; however, detection rates fell to 71% among the Black population.

These results highlight that although SMA carrier testing generally performs well and could be considered as a routine prenatal screen, SMA testing should be used cautiously in the Black population.