NGS-based spinal muscular atrophy carrier screening of 10,585 diverse couples in China: a pan-ethnic study

Eur J Hum Genet. 2021 Jan;29(1):194-204. doi: 10.1038/s41431-020-00714-8. Epub 2020 Sep 3.

Abstract

In this study, we performed a spinal muscular atrophy carrier screening investigation with NGS-based method. First, the validation for NGS-based method was implemented in 2255 samples using real-time PCR. The concordance between the NGS-based method and real-time PCR for the detection of SMA carrier and patient were up to 100%. Then, we applied this NGS-based method in 10,585 self-reported normal couples (34 Chinese ethnic groups from 5 provinces in South China) for SMA carrier screening. The overall carrier frequency was 1 in 73.8 (1.4%). It varied substantially between ethnic groups, highest in Dai ethnicity (4.3%), and no significant difference was found between five provinces. One couple was detected as carriers with an elevated risk of having an SMA affected baby. The distribution of SMN1:SMN2 genotype was also revealed in this study. Among the individuals with normal phenotype, the exon 7 copy-number ratio of SMN1 to SMN2 proved the gene conversion between them. With NGS-based method, we investigated SMA carrier status in Chinese population for the first time, and our results demonstrated that it is a promising alternative for SMA carrier screening and could provide data support and reference for future clinical application.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • China
  • Ethnicity / genetics*
  • Female
  • Gene Conversion
  • Gene Frequency*
  • Genetic Carrier Screening / statistics & numerical data*
  • High-Throughput Nucleotide Sequencing / statistics & numerical data
  • Humans
  • Male
  • Muscular Atrophy, Spinal / ethnology
  • Muscular Atrophy, Spinal / genetics*
  • Sequence Analysis, DNA / statistics & numerical data
  • Survival of Motor Neuron 1 Protein / genetics
  • Survival of Motor Neuron 2 Protein / genetics

Substances

  • SMN1 protein, human
  • SMN2 protein, human
  • Survival of Motor Neuron 1 Protein
  • Survival of Motor Neuron 2 Protein