TABLE 1:

Clinical, neuropsychologic, and molecular data from 17 patients

	Mean or %	SD	No. of Patients
Age at MR imaging	68 years	5.5	17
Age at tremor onset	58.3 years	3.9	15
Age at ataxia onset	61.6 years	5.6	15
Significant impairment
Writing	89%		17
Walking	50%		17
Tremor	89%		17
Character of tremor
Kinetic > postural	100%		15
Discrete resting tremor	58%		15
Gait ataxia	89%		17
Dyssynergia	72%		17
Tone, mild increase	47%		14
Neuropsychologic data
VIQ	98	16	6
PIQ	83	17	6
FSIQ	91	18	6
Executive function deficits	100%		6
VIQ < 85	33%		6
PIQ < 85	66%		6
Impotence	100%		6
CGG repeat	86	10	17
FMRP level	77.5%^*	9%	6
mRNA level	2.53-fold^†	0.48	6

* Percentage of lymphocytes that are positive for fragile X mental retardation 1 protein immuno-cytochemical staining for fragile X mental retardation 1 protein (19,46).
† 2.53-fold increase over normal (16,46).
Note.—VIQ indicates verbal intelligence quotient; PIQ, performance intelligence level; FSIQ, full scale intelligence quotient; FMRP, fragile X mental retardation 1 protein; mRNA, messenger RNA.