ANO3, a member of the anoctamin (TMEM16) protein family, is involved in functions such as ion transport and phospholipid scrambling [5]. It has been associated with the calcium homeostasis pathway, and its malfunction may disrupt normal cellular functions [3]. Mutations in ANO3 are relevant as they can lead to various genetic diseases, highlighting its biological importance [5].

Mutations in ANO3 are a rare cause of autosomal dominant isolated or combined dystonia, mainly presenting in adulthood. A study of a new ANO3 family found that a heterozygous p.G6V variant in ANO3 was identified in all affected subjects, with younger patients displaying a more severe phenotype, likely due to variants near the scrambling domain [1]. Another study described a 3-year-old girl with distal myoclonic dystonia and a de novo missense ANO3 variant, along with psychomotor regression and brain atrophy, suggesting that missense mutations in ANO3 may underlie complex disorders with early psychomotor regression and dystonia [2]. In a Chinese cohort, four different ANO3 variants were identified in dystonia patients, and a novel missense mutation in a teenaged girl with generalized dystonia was classified as "likely pathogenic" and she responded well to deep brain stimulation [4]. Overall, ANO3 mutations seem to expand the mutational and clinical spectrum of dystonia 24 (DYT24) [4].

In conclusion, ANO3 is crucial for normal cellular function through its role in ion transport and phospholipid scrambling. Studies on ANO3-related mutations, especially in the context of dystonia, have provided insights into the genotype-phenotype characteristics of the disorder. These findings contribute to understanding the pathogenesis of dystonia and may potentially lead to new treatment strategies for this movement disorder.