Nevo Yoram, Muntoni Francesco, Sewry Caroline, Legum Cyril, Kutai Miriam, Harel Shaul, Dubowitz Victor
Pediatric Neuromuscular Service, Institute for Child Development, Pediatric Neurology Unit, Tel Aviv, Israel.
Isr Med Assoc J. 2003 Feb;5(2):94-7.
The prediction that Duchenne muscular dystrophy patients have out-of-frame deletions and Becker muscular dystrophy patients have in-frame deletions of the dystrophin gene holds well in the vast majority of cases. Large in-frame deletions involving the rod domain only have usually been associated with mild (BMD) phenotype.
To describe unusual cases with large in-frame deletions of the rod-shaped domain of the dystrophin gene associated with severe (Duchenne) clinical phenotype
Screening for dystrophin gene deletion was performed on genomic DNA by using multiplex polymerase chain reaction. Needle muscle biopsies from the quadriceps were obtained using a Bergström needle. The biopsies were stained with histologic and histochemical techniques as well as monoclonal antibodies to dystrophin 1, 2 and 3.
In three children with large in-frame deletions of the rod domain (exons 10-44, 13-40 and 3-41), early-onset weakness and a disease course suggested the DMD phenotype.
This observation emphasizes the uncertainty in predicting the Becker phenotype in a young patient based on laboratory evaluation, and that the clinical picture should always be considered.
杜氏肌营养不良症患者存在肌营养不良蛋白基因的框外缺失，而贝克型肌营养不良症患者存在该基因的框内缺失，这一预测在绝大多数情况下是成立的。仅涉及杆状结构域的大型框内缺失通常与轻度（贝克型肌营养不良症）表型相关。
描述肌营养不良蛋白基因杆状结构域大型框内缺失且伴有严重（杜氏）临床表型的罕见病例。
采用多重聚合酶链反应对基因组DNA进行肌营养不良蛋白基因缺失筛查。使用贝格斯特龙针从股四头肌获取肌肉活检样本。活检样本采用组织学、组织化学技术以及针对肌营养不良蛋白1、2和3的单克隆抗体进行染色。
在3名患有杆状结构域大型框内缺失（外显子10 - 44、13 - 40和3 - 41）的儿童中，早期出现的肌无力及病程提示为杜氏肌营养不良症表型。
这一观察结果强调了基于实验室评估预测年轻患者贝克型表型存在不确定性，且始终应考虑临床症状。
