Service de Génétique Médicale, CHU Bordeaux, Bordeaux, Bordeaux, France.
Centre de Référence Maladies Rares Neurogénétique, Service de Génétique Médicale, Bordeaux, France.
Eur J Hum Genet. 2021 Jul;29(7):1158-1163. doi: 10.1038/s41431-021-00847-4. Epub 2021 May 6.
Hereditary spastic paraplegias (HSP) are heterogeneous disorders, with more than 70 causative genes. Variants in SPAST are the most frequent genetic etiology and are responsible for spastic paraplegia type 4 (SPG4). Age at onset can vary, even between patients from the same family, and incomplete penetrance is described. Somatic mosaicism is extremely rare with only three patients reported in the literature. We report here SPAST mosaic variants in four unrelated patients. We confirm that mosaicism in SPAST is a very rare event with only four identified cases on more than 300 patients with a SPAST variant previously described by our clinical diagnostic laboratory.
遗传性痉挛性截瘫（HSP）是一种异质性疾病，有 70 多个致病基因。SPAST 中的变异是最常见的遗传病因，导致痉挛性截瘫 4 型（SPG4）。发病年龄可有所不同，即使是同一家庭的患者之间也是如此，并且存在不完全外显率的情况。体细胞嵌合极为罕见，文献中仅报道了 3 例患者。我们在此报告 4 例无关联患者的 SPAST 嵌合变异。我们证实，SPAST 嵌合是一种非常罕见的事件，在我们临床诊断实验室之前描述的 300 多例 SPAST 变异患者中，仅发现了 4 例。
