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Notable Carrier Risks for Individuals Having Two Copies of SMN1 in Spinal Muscular Atrophy Families with 2-copy Alleles: Estimation Based on Chinese Meta-analysis Data

  • Original Research
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Journal of Genetic Counseling

Abstract

Spinal muscular atrophy is an autosomal recessive neuromuscular disease mainly caused by homozygous deletion of SMN1. The 2-copy SMN1 allele may present in the families of SMA patients with homozygous deletion of SMN1, one of whose parents has two SMN1 copies. In such families, individuals having two SMN1 copies still have a chance to be “2 + 0” carriers. In this study, the risks for the parents, fetuses and other siblings having two SMN1 copies to be “2 + 0” carriers were estimated based on Chinese meta-analysis data and turned out to be rather striking. Our findings would help to optimize genetic counseling regarding spinal muscular atrophy.

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Acknowledgments

We thank Professor Xiangmin Xu and Jianjiu Chen for helpful discussions.

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Authors and Affiliations

  1. State Key Laboratory of Medical Genetics, Central South University, 110 Xiangya Road, Changsha, Hunan, 410078, China

    Xianda Wei, Hu Tan, Pu Yang, Rui Zhang, Bo Tan, Yue Zhang, Libin Mei, Desheng Liang & Lingqian Wu

  2. Hunan Jiahui Genetics Hospital, 110 Xiangya Road, Changsha, Hunan, China

    Desheng Liang & Lingqian Wu

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  1. Xianda Wei
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  2. Hu Tan
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  3. Pu Yang
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  4. Rui Zhang
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  5. Bo Tan
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Correspondence to Desheng Liang or Lingqian Wu.

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Funding

This work was funded by the Ministry of Science and Technology of the People’s Republic of China (Grant No. 2014FY110700).

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The authors of the article declare that they have no conflict of interest.

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This article does not contain any studies with human participants or animals performed by any of the authors.

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This article is a meta-analysis and does not contain any studies with human participants. Therefore, an informed consent was not necessary.

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Wei, X., Tan, H., Yang, P. et al. Notable Carrier Risks for Individuals Having Two Copies of SMN1 in Spinal Muscular Atrophy Families with 2-copy Alleles: Estimation Based on Chinese Meta-analysis Data. J Genet Counsel 26, 72–78 (2017). https://doi.org/10.1007/s10897-016-9980-7

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