We performed an observational, natural history study of males with in‐frame dystrophin gene deletions causing Becker muscular dystrophy (BMD). A prospective natural history study collected longitudinal medical, strength, and timed function assessments. Eighty‐three participants with genetically confirmed BMD were enrolled (age range 5.6–75.4 years). Lower extremity function and the percentage of participants who retained ambulation declined across the age span. The largest single group of participants had in‐frame deletions that corresponded to an out‐of‐frame deletion treated with an exon 45 skip to restore the reading frame. This group of 54 participants showed similarities in baseline motor functional assessments when compared to the group of all others in the study. A prospective natural history cohort with in‐frame dystrophin gene deletions offers the potential to contribute to clinical trial readiness for BMD and to analyze therapeutic benefit of exon skipping for Duchenne muscular dystrophy.

中文翻译：

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CINRG Becker 自然历史研究：基线特征。

我们对导致 Becker 肌营养不良症 (BMD) 的框内肌营养不良蛋白基因缺失的男性进行了观察性自然史研究。一项前瞻性自然史研究收集了纵向医疗、力量和定时功能评估。招募了 83 名经基因证实 BMD 的参与者（年龄范围 5.6-75.4 岁）。下肢功能和保持步行的参与者百分比在整个年龄范围内都在下降。最大的一组参与者具有框内缺失，对应于用外显子 45 跳跃处理以恢复阅读框的框外缺失。与研究中的所有其他组相比，这组 54 名参与者在基线运动功能评估方面表现出相似之处。