目的 探讨脊髓性肌萎缩伴先天性骨折2型（SMABF 2）的临床特征。方法 回顾分析2例因ASCC 1基因 变异致SMABF 2患儿的临床资料，并复习相关文献。结果 2例患儿为相隔4年出生的同胞兄弟，弟弟为先证者。2例患 儿均因生后呼吸浅弱、肌张力低下、多发性关节挛缩收入院，均因呼吸衰竭予有创呼吸支持；均有手指屈曲畸形，双腕关 节、双侧膝关节过伸，挛缩，双足内翻。X线摄片均示全身骨骼发育差，骨质菲薄，肋骨细小；先证者为左胫腓骨骨折，先 证者哥哥为右肱骨中段骨折。先证者全外显子测序分析示ASCC 1基因（NM_ 0011988002 . 2，OMIM：616867）存在未见报 道的纯合错义变异c. 913 C>T （p. 305 His>Tyr），位于10 q 22 . 1，父母亲为杂合携带。中国内地尚无ASCC 1基因变异报道。 结论 SMABF 2系常染色体隐性遗传病，ASCC1是其致病基因。

Objective To explore the clinical features of spinal muscular atrophy with congenital bone fractures- 2 (SMABF 2 ). Methods The clinical data of 2 newborns with SMABF 2 caused by ASCC 1 gene variation were retrospectively analyzed and the relevant literatures were reviewed. Results Two children were siblings with a 4 -year age difference, and the younger brother was the proband. They were admitted to the hospital due to postnatal respiratory distress, hypotonia and arthrogryposis multiplex congenital. Because of respiratory failure, two newborns were given mechanical ventilation support after birth. Two children had finger flexion deformity, hyperextension and contracture of bilateral wrist joint and knee joint and bilateral club-foot. Whole body X-ray images showed poor skeletal development, rarefaction of bone, thin and gracile ribs. The proband suffered a fracture of the left tibiofibula, and his older brother suffered a fracture of the middle part of the right humerus. The whole exon sequencing analysis of the proband showed a novel homozygous missense variation of c. 913 C>T (p. 305 His>Tyr) in the ASCC 1 gene (NM_ 0011988002 . 2 , OMIM: 616867 ), which was located at 10 Q 22 . 1 . Both parents are carriers of heterozygous variation. ASCC 1 gene variation has not been reported in China. Conclusion SMABF 2 is an autosomal recessive inheritance disease, and ASCC 1 gene variation is the pathogenic factor.