TABLE 1:

Clinical History and Present Findings

Finding	Patient
Finding	1	2	3	4	5	6	7
Sex	Male	Male	Female	Female	Female	Male	Male
Year of birth	1993	1991	1989	1989	1989	1983	1980
No. siblings
Affected	0	0	0	0	0	0	0
Unaffected	0	0	1	0	0	2	2
Consanguinity of parents	No	No	No	No	No	No	No
Ethnic background	Caucasian	Caucasian	Caucasian	Caucasian	Asian-Caucasian	Caucasian	Caucasian
Age at presentation	1 y	1.5 y	2 y	1 y	2 mo	2 mo	3 y
Presenting sign	Delayed motor development	Delayed motor development	Delayed motor development	Delayed motor development	Poor vision	Poor vision	Motor deterioration
Initial motor development	Delayed	Delayed	Delayed	Normal	Very little^*	Very little^*	Normal
Supported walking	At 3.5 y	At 18 mo	At 20 mo	At 12 mo	No	No	At 12 mo
Unsupported walking	No	No	At 2.5 y	No	No	No	At 14 mo
Onset of motor deterioration	At 1.5 y	At 2 y	At 6 y	At 2 y	In infancy	At 5 mo	At 3 y
Loss of supported walking ability	None	At 4.5 y	At 6 y	At 2.5 y	NA	NA	At 10 y
Motor signs
Spasticity	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Ataxia	Yes, mild	Yes	Yes	Yes	Not testable	Not testable	Yes, mild
Tremor	No	Yes	Yes	No	No	No	Yes
Choreoathetosis	No	Yes	Yes	Yes	Yes	No	Yes
Dystonia	Yes	Yes	Yes	Yes	Yes	No	Yes
Rigidity	Yes	Yes	No	Yes	Yes	Yes	Yes
Dysarthria	Anathria	Yes	Yes	Anarthria	Anarthria	Anathria	Yes
Intelligence	Mental retardation	Learning difficulties	Learning difficulties	Learning difficulties	Not testable	Not testable	Learning difficulties
Cognitive decline	No	Questionable	Questionable	No	Not testable	Not testable	Mild
Epilepsy	No	No	No	No	Few seizures	One seizure	No
Vision	Normal	Normal	Normal	Normal	Decreased, pale optic discs	Decreased, pale optic discs	Normal
Hearing	Normal	Normal	Normal	Normal	Normal	Normal	Normal
Head circumference	−2 SD	Normal	Normal	Normal	<2 SD	<2 SD	Normal
Stature	<2 SD	Normal	Normal	Normal	<2 SD	<2 SD	Normal

Note.—NA indicates not applicable.
* Holding objects.