Table 1 Disease characteristics of the six patients.

	Case 1	Case 2	Case 3	Case 4	Case 5	Case 6
Sex/age (years)	M/58	F/50	M/29	F/44	M/23	F/58
Age at onset (years)	54	24	21	39	21	8
Family history	−	AD	AD	—	—	—
Presentation	CA	Dystonia	Dystonia	CA	Dystonia	CA/dystonia
Dystonia
Cranial	+	–	–	+	–	–
Cervical	+	+	+	+	+	+
Axial	–	+	–	–	–	–
Brachial	–	+	–	+/–	–	+
Crural	–	+	–	–	–	–
Cerebellar signs
Eyes	+	+	+	+	–	+
Speech	+	+	+/–	+	+	+
Gait	+	+	–	+	+/–	+
Arms	+	+	+	+	+	+
Legs	+	+	–	+	+	+
Ataxia disease stage	1	1	1	1	1	1
MRI of the brain
Cerebellar atrophy	Mild/global	Severe/global (fig 1)	Severe/global	Normal	Moderate/global	Moderate/global
Brainstem	Mild atrophy	Normal	Normal	Normal	Normal	Normal
Basal ganglia	Normal	Normal	Normal	Normal	Normal	Normal
White matter	Normal	Normal	Normal	Normal	Normal	Normal

AD, autosomal dominant; CA, cerebellar ataxia; F, female; M, male; +, positive or present; −, negative or absent; +/‐ subtle or equivocal.

Ataxia disease stages includes scores 0 (no ataxia), 1 (ataxia, but walking independently), 2 (permanently dependent on walking aids), 3 (permanently dependent on wheelchair) and 4 (death).³