MAPT mutations were the first discovered genetic cause of frontotemporal dementia (FTD) in 1998. Since that time, over 60 MAPT mutations have been identified, usually causing behavioral variant FTD and/or parkinsonism clinically. We describe 2 novel MAPT mutations, D252V and G389_I392del, each presenting in a patient with behavioral variant FTD and associated language and cognitive deficits. Neuroimaging revealed asymmetrical left greater than right temporal lobe atrophy in the first case, and bifrontal atrophy in the second case. Disease duration was 8 years and 5 years, respectively. Postmortem examination in both patients revealed a 3-repeat predominant tauopathy, similar in appearance to Pick's disease. These 2 mutations add to the literature on genetic FTD, both presenting with similar clinical and imaging features to previously described cases, and pathologically showing a primary tauopathy similar to a number of other MAPT mutations.

中文翻译：

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两例经病理证实的 MAPT 基因新突变导致额颞叶痴呆

MAPT 突变是 1998 年首次发现的额颞叶痴呆 (FTD) 的遗传原因。从那时起，已经确定了 60 多个 MAPT 突变，通常会导致临床上的行为变异 FTD 和/或帕金森病。我们描述了 2 个新的 MAPT 突变，D252V 和 G389_I392del，每个突变都出现在一个患有行为变异 FTD 和相关语言和认知缺陷的患者中。神经影像学显示在第一种情况下不对称的左侧大于右侧颞叶萎缩，以及第二种情况下的双额叶萎缩。病程分别为8年和5年。两名患者的尸检均显示 3 次重复为主的 tau 蛋白病，外观与皮克病相似。这两个突变增加了遗传 FTD 的文献，