Molecular analysis of the VPS13A gene in the proband A-II:4 confirmed the ChAc diagnosis and revealed the presence of three variants: c.3817C>T, c.1114_1115delAA and c.3592A>C; the last two were found to be in cis on the maternal copy of the gene (Supplementary Figure S1). This evidence concerns the gene VPS13A and Choreoacanthocytosis.