Table 2 Summary of data based on exclusion of 28 samples for which repeat analysis was absent, partial or discrepant by one CAG repeat.

CAG repeat size	Number in study	Affected	Mean age of onset (years)	Range in age of onset (years)	Unaffected	Mean age (years)	Range (years)
36	18	9	59.4	38–79	9	42.5	23–68
37	39	19	60.6	48–74	20	48.5	21–85
38	46	13	52.0	40–75	33	48.0	25–76
39	73	35	64.1	38–89	38	48.7	20–79
Total	176	76			100