摘要目的:探讨胚胎植入前单基因病检测在特殊的脊髓性肌萎缩症(SMA)2＋0型中的临床应用。方法:回顾性分析2020年10月19日于广州医科大学附属第三医院就诊的1例特殊SMA家系资料。利用多重连接探针扩增技术和分子标签连锁分析对夫妇双方及其胎儿进行 SMN1基因型的鉴定，并借助二代测序(NGS)、分子标签连锁分析以及染色体微阵列分析3种方法对该夫妇的11枚胚胎进行单体型分析和结果验证。 结果:明确了女方为特殊的 SMN1[2＋0]携带型，产前诊断确定胎儿为SMA患者，最终通过行胚胎植入前单基因病遗传检测成功筛选出4枚未携带 SMN1致病变异和X染色体缺失的胚胎。 结论:胚胎植入前单基因病遗传检测能够有效阻断上述SMA 2＋0型患者的特殊遗传变异的传递，为家系再生育提供指导。

abstractsObjective:To explore the clinical application of preimplantation genetic testing for monogenic disorders (PGT-M) in an unique case with Spinal muscular atrophy (SMA) type 2+ 0.Methods:A special SMA family presented at the Third Affiliated Hospital of Guangzhou Medical University on October 19, 2020 was selected as the study subject. Multiple ligation-dependent probe amplification (MLPA) and molecular tagging linkage analysis were carried out to identify the SMN1 genotype of the couple and their fetus. Subsequently, next-generation sequencing (NGS), molecular tagging linkage analysis, and chromosomal microarray analysis were employed to determine the haplotypes and validate the result of PGT-M on the 11 embryos derived for the couple. Results:The female partner was identified as a carrier of the rare SMN1[2+ 0] variant, and prenatal diagnosis confirmed the fetus to be affected by SMA. Ultimately, PGT-M has successfully selected four embryos free from the pathogenic SMN1 variants and X chromosome deletion. Conclusion:PGT-M can effectively prevent the transmission of rare genetic variants such as the SMA 2+ 0 subtype in the families. Above finding has provided guidance for genetic counseling and family planning for the couple.