Covone A E, Lerone M, Romeo G
Laboratorio di Genetica Molecolare, Istituto G. Gaslini, Genova, Italy.
Hum Genet. 1991 Jul;87(3):353-60. doi: 10.1007/BF00200919.
The molecular analysis of 127 DMD/BMD patients showed that 73 of them (57%) had deletions in the dystrophin gene. Two different methods were used in this study: (a) hybridization of HindIII-digested genomic DNA with nine cDNA probes corresponding to the entire 14kb cDNA of the DMD gene; and (b) simultaneous amplification of nine exons of the DMD gene (multiplex DNA amplification) by the polymerase chain reaction (PCR). When the deletion breakpoints of the intragenic deletions were analyzed with regard to their phenotypic consequences, nine patients were found to represent exceptions to the reading-frame hypothesis. Information regarding mental development was also available for 61 of the 73 deleted patients and for 34 of the 54 non-deleted ones. The proportion of mentally retarded patients was found to be similar in the two groups (deleted, 15%; non-deleted, 18%). Finally, in one family, a junction fragment present in the patient was not found in the peripheral blood DNA of the mother but was present in the sister, thus indicating germline mosaicism in the mother.
对127例杜氏肌营养不良症/贝克型肌营养不良症患者进行的分子分析显示，其中73例（57%）的抗肌萎缩蛋白基因存在缺失。本研究采用了两种不同的方法：（a）用与杜氏肌营养不良症基因全长14kb cDNA对应的9个cDNA探针与经HindIII酶切的基因组DNA进行杂交；（b）通过聚合酶链反应（PCR）对杜氏肌营养不良症基因的9个外显子进行同步扩增（多重DNA扩增）。当分析基因内缺失的缺失断点的表型后果时，发现9例患者是读码框假说的例外情况。在73例缺失患者中的61例以及54例未缺失患者中的34例中也可获得有关智力发育的信息。发现两组中智力发育迟缓患者的比例相似（缺失组为15%；未缺失组为18%）。最后，在一个家族中，患者体内存在的一个连接片段在母亲的外周血DNA中未发现，但在其妹妹体内存在，从而表明母亲存在生殖系嵌合体现象。
