Tremor in Primary Monogenic Dystonia.

PURPOSE OF REVIEW: Tremor is an important phenotypic feature of dystonia with wide variability in the reported prevalence ranging from 14 to 86.67%. This variability may be due to the types of dystonia patients reported in different studies. This article reviews research articles reporting tremor in primary monogenic dystonia.

RECENT FINDINGS: We searched the MDS gene data and selected all research articles reporting tremor in primary monogenic dystonia. Tremor was reported in nine dystonia genes, namely DYT-HPCA, DYT-ANO3, DYT-KCTD17, DYT-THAP1, DYT-PRKRA, DYT-GNAL, DYT-TOR1A, DYT-KMT2B, and DYT-SGCE in the descending order of its frequency. HPCA gene mutation is rare, but all reported patients had tremor. Similarly, tremor was reported in eight genes associated with dystonia parkinsonism, namely DYT-SLC6A3, DYT-TH, DYT-SPR, DYT-PTS, DYT-GCH1, DYT-TAF1, DYT-QDPR, and DYT-SCL30A10 in the descending order of its prevalence. DYT-HPCA and DYT-ANO3 gene showed the highest prevalence of tremor in isolated dystonia, and DYT-SLC6A3 has the highest prevalence of tremor in combined dystonia.