A Family with Epilepsy and Dyskinesia due to Homozygous PRRT2 Gene Mutation

Abstract

Proline-rich transmembrane protein 2 (PRRT2) plays an important role in the central nervous system, and mutations in the gene are implicated in various neurological disorders. Variants in PRRT2 (OMIM*614386) can manifest as a variety of clinical phenotypes, including convulsions with paroxysmal choreoathetosis, paroxysmal kinesigenic dyskinesia (PKD), benign familial infantile seizure, and hemiplegic migraine. Here, we report a family with a homozygous PRRT2 variant with benign familial infantile epilepsy and PKD attacks, summarize the clinical characteristics of neurological diseases related to the PRRT2 gene, and explore the therapeutic effects and urge that these patients be treated with acetazolamide during the dyskinesia attacks.

Keywords

proline-rich transmembrane protein 2 - benign familial infantile epilepsy - paroxysmal kinesigenic dyskinesia - self-limited infantile epilepsy - antiseizure medication

Authors' Contributions

Both authors contributed to the study's conceptualization and data collection, as well as to the drafting, development, and finalization of the manuscript. They both approved the final version of the manuscript.

Patient Consent

The authors confirm that they obtained the appropriate consent from the parents of the reported cases to report anonymously. All efforts were made to avoid possible identification of the reported individuals.

Compliance with Ethical Principles

No prior ethical approval is required for single-case reports or small case series, provided that consent was obtained from the patients or guardians.

Publication History

Article published online:
16 July 2025

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