Rowland L P
H. Houston Merritt Clinical Research Center for Muscular Dystrophy and Related Diseases, Columbia-Presbyterian Medical Center, New York 10032-3784.
Brain. 1988 Jun;111 ( Pt 3):479-95. doi: 10.1093/brain/111.3.479.
Molecular genetics has transformed clinical concepts of Duchenne muscular dystrophy (DMD) in several different ways. (1) The disease can now be defined as a myopathy due to mutation at Xp21, a specific locus on the short arm of the X chromosome. (2) As a consequence of that discovery, any myopathy due to mutation at Xp21 should be a variant of DMD and should affect the same gene product. Moreover, any myopathy due to mutation at a location other than Xp21 should affect some other gene product. (3) For these reasons, DNA analysis is now needed for clinical diagnosis of muscle disease. (4) Xp21 myopathies may be mild or severe, may occur in females even though X-linked, and may be manifest only by high serum levels of creatine kinase. (5) Mental retardation is not consistently related to diseases that are encoded at Xp21. The association of mental retardation with DMD may be due to mutation in a separate gene near that for DMD. Concepts may soon be altered again as we learn about the affected gene product (dystrophin) and its role in these diseases.
分子遗传学已通过多种不同方式改变了杜兴氏肌营养不良症（DMD）的临床概念。（1）现在可以将该疾病定义为由于X染色体短臂上的特定基因座Xp21发生突变而导致的肌病。（2）基于这一发现，任何因Xp21突变导致的肌病都应是DMD的一种变体，并且应影响相同的基因产物。此外，任何因Xp21以外位置的突变导致的肌病都应影响其他一些基因产物。（3）出于这些原因，现在肌肉疾病的临床诊断需要进行DNA分析。（4）Xp21肌病可能轻微或严重，即使是X连锁的也可能发生在女性身上，并且可能仅表现为血清肌酸激酶水平升高。（5）智力迟钝与Xp21编码的疾病并无始终如一的关联。智力迟钝与DMD的关联可能是由于DMD基因附近的另一个单独基因发生了突变。随着我们对受影响的基因产物（抗肌萎缩蛋白）及其在这些疾病中的作用的了解，这些概念可能很快会再次改变。
