Abstract

Background:

Right temporal variant frontotemporal dementia (rtvFTD) has been generally considered as a right sided variant of semantic variant primary progressive aphasia (svPPA), which is a genetically sporadic disorder. Recently, we have shown that rtvFTD has a unique clinical syndrome compared to svPPA and behavioral variant frontotemporal dementia.

Objective:

We challenge the assumption that rtvFTD is a sporadic, non-familial variant of FTD by identifying potential autosomal dominant inheritance and related genes in rtvFTD.

Methods:

We collected all subjects with a diagnosis of FTD or primary progressive aphasia who had undergone genetic screening (n = 284) and subsequently who had a genetic variant (n = 48) with a diagnosis of rtvFTD (n = 6) in 2 specialized memory clinics.

Results:

Genetic variants in FTD related genes were found in 33% of genetically screened rtvFTD cases; including MAPT (n = 4), GRN (n = 1), and TARDBP (n = 1) genes, whereas only one svPPA case had a genetic variant in our combined cohorts. Additionally, 4 out of 6 rtvFTD subjects had a strong family history for dementia.

Conclusion:

Our results demonstrate that rtvFTD, unlike svPPA, is not a pure sporadic, but a heterogeneous potential genetic variant of FTD, and screening for genetic causes for FTD should be performed in patients with rtvFTD.

中文翻译：

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额颞叶痴呆的正确时间变异不是遗传散发的：病例系列

摘要

背景：

右颞叶变异性额颞叶痴呆 (rtvFTD) 通常被认为是语义变异原发性进行性失语症 (svPPA) 的右侧变异，svPPA 是一种遗传散发性疾病。最近，我们已经表明，与 svPPA 和行为变异额颞叶痴呆相比，rtvFTD 具有独特的临床综合征。

客观的：

我们通过识别 rtvFTD 中潜在的常染色体显性遗传和相关基因来挑战 rtvFTD 是 FTD 的一种散发性、非家族性变异的假设。

方法：

我们收集了所有被诊断为 FTD 或原发性进行性失语症的受试者，他们 在 2 个专门的记忆诊所接受了基因筛查 ( n  = 284)，随后有遗传变异 ( n  = 48) 并被诊断为 rtvFTD ( n = 6) .

结果：

在 33% 的基因筛查 rtvFTD 病例中发现了 FTD 相关基因的遗传变异；包括MAPT ( n  = 4)、GRN ( n  = 1) 和TARDBP ( n  = 1) 基因，而在我们的合并队列中只有一个 svPPA 病例具有遗传变异。此外，6 名 rtvFTD 受试者中有 4 名具有明显的痴呆家族史。

结论：

我们的研究结果表明，与 svPPA 不同，rtvFTD 不是单纯的散发性，而是 FTD 的异质潜在遗传变异，应在 rtvFTD 患者中进行 FTD 遗传原因筛查。