PDF(Pubmed)
Abstract：
Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is a neurodegenerative disorder caused by the ATXN3 CAG repeat expansion. Preimplantation genetic testing for monogenic disorders (PGT-M) of SCA3/MJD should include reliable repeat expansion detection coupled with high-risk allele determination using informative linked markers. One couple underwent SCA3/MJD PGT-M combining ATXN3 (CAG)n triplet-primed PCR (TP-PCR) with customized linkage-based risk allele genotyping on whole-genome-amplified trophectoderm cells. Microsatellites closely linked to ATXN3 were identified and 16 markers were genotyped on 187 anonymous DNAs to verify their polymorphic information content. In the SCA3/MJD PGT-M case, the ATXN3 (CAG)n TP-PCR and linked marker analysis results concurred completely. Among the three unaffected embryos, a single embryo was transferred and successfully resulted in an unaffected live birth. A total of 139 microsatellites within 1 Mb upstream and downstream of the ATXN3 CAG repeat were identified and 8 polymorphic markers from each side were successfully co-amplified in a single-tube reaction. A PGT-M assay involving ATXN3 (CAG)n TP-PCR and linkage-based risk allele identification has been developed for SCA3/MJD. A hexadecaplex panel of highly polymorphic microsatellites tightly linked to ATXN3 has been developed for the rapid identification of informative markers in at-risk couples for use in the PGT-M of SCA3/MJD.
摘要：
脊髓小脑共济失调3型/Machado-Joseph病（SCA3/MJD）是由ATXN3CAG重复扩增引起的神经退行性疾病。SCA3/MJD单基因疾病（PGT-M）的植入前遗传测试应包括可靠的重复扩增检测以及使用信息连锁标记的高风险等位基因确定。一对夫妇在全基因组扩增的滋养外胚层细胞上进行了SCA3/MJDPGT-M结合ATXN3（CAG）n三联体引发的PCR（TP-PCR）和定制的基于连锁的风险等位基因基因分型。鉴定了与ATXN3紧密相关的微卫星，并在187个匿名DNA上对16个标记进行了基因分型，以验证其多态性信息含量。在SCA3/MJDPGT-M案例中，ATXN3（CAG）nTP-PCR和连锁标记分析结果完全一致。在三个未受影响的胚胎中，移植了单个胚胎，并成功地导致了不受影响的活产。在ATXN3CAG重复的上游和下游1Mb内总共鉴定出139个微卫星，并且在单管反应中成功地共扩增了每侧的8个多态性标记。已针对SCA3/MJD开发了涉及ATXN3（CAG）nTP-PCR和基于连锁的风险等位基因鉴定的PGT-M测定法。已开发出与ATXN3紧密相连的高度多态微卫星的十六进制面板，用于快速鉴定处于危险中的夫妇中的信息标记，以用于SCA3/MJD的PGT-M。
