トロイヤー症候群における小人症：SPG20複合ヘテロ接合変異を有する一家と文献レビュー

Dwarfism in Troyer syndrome: a family with SPG20 compound heterozygous mutations and a literature review.

• Hanting Liang
• Hui Miao
• Hongbo Yang
• Fengying Gong
• Shi Chen
• Linjie Wang
• Huijuan Zhu
• Hui Pan

抄録

トロイアー症候群は、痙性麻痺、構音障害、遠位筋萎縮、低身長を特徴とする常染色体劣性疾患である。最近，兄と妹の2人の兄弟が「低身長と知的障害」を主訴に当院に入院した．姉のSPG20遺伝子の全エクソームシークエンシングの結果、姉のSPG20遺伝子には複合ヘテロ接合性の突然変異c.364_365delAT（p.Met122Valfs 2）とc.892delA（p.Thr298Glnfs 30）が存在することが判明しました。標的検査の結果、兄弟は姉妹と同じ遺伝子型を持ち、前者の突然変異は父親に由来し、後者の突然変異は母親に由来することが明らかになった。まとめると、これはSPG20複合ヘテロ接合体変異に起因する家族におけるトロイヤー症候群の最初の報告である。また、新規なSPG20変異、すなわちc.892delA（p.Thr298Glnfs 30）が発見された。さらに、これらのトロイヤー症候群患者の身長と臨床的特徴をまとめ、SPG20の既知のすべての病原性変異の簡単なレビューを提供する。

Troyer syndrome is an autosomal recessive disease characterized by spastic paralysis, dysarthria, distal amyotrophy, and short stature. Recently, two siblings (an older brother and a younger sister) were admitted to our hospital for the chief complaints of "short stature and intellectual disability." Through whole exome sequencing of the sister, who is the proband, it was found that her SPG20 gene had compound heterozygous mutations: c.364_365delAT (p.Met122Valfs 2) and c.892delA (p.Thr298Glnfs 30). Target testing revealed that the brother had the same genotype as the sister, and the former mutation originated from the father, while the latter mutation originated from the mother. In summary, this is the first report of Troyer syndrome in a family caused by SPG20 compound heterozygous mutations. A novel SPG20 mutation was found, namely c.892delA (p.Thr298Glnfs 30). In addition, we also summarize these Troyer syndrome patients' heights and their clinical characteristics, and provide a brief review of all known pathogenic mutations of SPG20.

© 2019 New York Academy of Sciences.