Fibrodysplasia Ossificans Progressiva (FOP) is a rare autosomal dominant disease characterized by congenital malformation of the great toes and progressive heterotopic ossification of soft tissues leading to cumulative disability. The genetic cause of FOP are mutations in the ACVR1 gene that encodes a type I receptor of Bone Morphogenetic Proteins. The most recurrent mutation in FOP patients is R206H affecting the Glycine-Serine rich domain and causing the hyper-activation of the receptor and the responsivity to the non-canonical ligand, Activin A.

中文翻译：

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与 ACVR1 基因的新变体相关的进展性骨化纤维发育不良一例

进行性骨化纤维发育不良（FOP）是一种罕见的常染色体显性遗传疾病，其特征是大脚趾先天性畸形和软组织进行性异位骨化，导致累积性残疾。FOP 的遗传原因是编码骨形态发生蛋白 I 型受体的ACVR1基因突变。FOP 患者中最常见的突变是 R206H，它影响富含甘氨酸-丝氨酸的结构域并导致受体的过度活化和对非经典配体 Activin A 的反应。