Pathogenic ATXN2 (≥33, P = 0.046) and premutated ATXN1 (≥33, P = 0.0069) expansions showed nominally significant associations, and pathogenic CSTB expansions were nominally significantly associated when the recessive mode of inheritance associated with Unverricht–Lundborg disease was not considered (≥30, P = 0.021, Table S12). Here, CSTB is linked to glycogen storage disease VI.