Meola Giovanni, Sansone Valeria
Department of Neurology, University of Milan, IRCCS Policlinico San Donato, San Donato Hospital, Via Morandi 30, 20097 San Donato Milanese, Milan, Italy.
Muscle Nerve. 2007 Sep;36(3):294-306. doi: 10.1002/mus.20800.
Myotonic dystrophy types 1 (DM1) and 2 (DM2) are similar yet distinct autosomal-dominant disorders characterized by muscle weakness, myotonia, cataracts, and multiple organ involvement, including the brain. One key difference between DM1 and DM2 is that a congenital form has been described for DM1 only. Expression of RNA transcripts containing pathogenic repeat lengths produces defects in alternative splicing of multiple RNAs, sequesters specific repeat-binding proteins, and ultimately leads to developmentally inappropriate splice products for a particular tissue. Whether brain pathology in its entirety in adult DM1 and DM2 is caused by interference in RNA processing remains to be determined. This review focuses on the similarities and differences between DM1 and DM2 with respect to neuropsychological, neuropathological, and neuroimaging data relating to cerebral involvement, with special emphasis on the clinical relevance and social consequences of such involvement.
1型强直性肌营养不良症（DM1）和2型强直性肌营养不良症（DM2）是相似但又有区别的常染色体显性疾病，其特征为肌肉无力、肌强直、白内障以及包括大脑在内的多器官受累。DM1和DM2之间的一个关键区别在于，仅DM1有先天性形式的描述。含有致病重复长度的RNA转录本的表达会导致多种RNA的可变剪接出现缺陷，隔离特定的重复结合蛋白，并最终导致特定组织产生发育异常的剪接产物。成年DM1和DM2中整个脑部病变是否由RNA加工干扰引起仍有待确定。本综述重点关注DM1和DM2在与大脑受累相关的神经心理学、神经病理学和神经影像学数据方面的异同，特别强调这种受累的临床相关性和社会后果。
