Challenges in Establishing the Diagnosis of PRRT2 ‐Related Dystonia: Recurrent Pathogenic Variants in a Homopolymeric Stretch

Re-analysis of next-generation sequencing (NGS) data can help to resolve undiagnosed cases. 1 We report on two patients with dystonia to illustrate how stringent NGS-variant fi ltering criteria can lead to missed diagnoses in the context of variants lying in a homopolymeric nucleotide tract; at the same time, relaxing bioinformatic-fi lter settings can yield false-positive pathogenic variant-hits in the same homopolymeric stretch, further complicating the NGS-based diagnostic process.

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