Neurology Clinic, Clinical Center of Serbia, School of Medicine, University of Belgrade, Belgrade, Serbia.
Center for Human Molecular Genetics, Faculty of Biology, University of Belgrade, Belgrade, Serbia.
J Neuromuscul Dis. 2017;4(1):89-92. doi: 10.3233/JND-160192.
The aim of this study was to present a family co-segregating myotonic dystrophy type 1 (DM1) and 2 (DM2), and one member affected with neuromyelitis optica (NMO).
Index case underwent cataract surgery at age 39. Although she had no muscle symptoms, genetic testing revealed a DM2 mutation and a DM1 protomutation. The patient noticed difficulties in climbing stairs at age 47. Clinical examination showed mild muscle weakness, calf hypertrophy, mild myotonia and several multisystem signs. Patient's mother had DM1 protomutation and clinically exhibited only cataract. Two proband's sisters, one with DM2 mutation and another with DM2 mutation and DM1 protomutation, had a clinical presentation similar to the index case. In addition, the latter also developed NMO.
Our findings suggest that screening for both DM1 and DM2 should be done and a positive result in either gene should not be an indication to stop screening, but to move to the other gene.
本研究旨在介绍一个家系共分离了肌强直性营养不良 1 型（DM1）和 2 型（DM2），以及一名患有视神经脊髓炎（NMO）的患者。
索引病例在 39 岁时接受了白内障手术。尽管她没有肌肉症状，但基因检测显示 DM2 突变和 DM1 前突变。患者在 47 岁时注意到爬楼梯困难。临床检查显示轻度肌肉无力、小腿肥大、轻度肌强直和几个多系统体征。患者的母亲有 DM1 前突变，临床仅表现为白内障。两个先证者的姐妹，一个有 DM2 突变，另一个有 DM2 突变和 DM1 前突变，临床表现与索引病例相似。此外，后者还发生了 NMO。
我们的发现表明，应同时筛查 DM1 和 DM2，并且任何一个基因的阳性结果都不应成为停止筛查的指征，而应进一步筛查另一个基因。
