Table 4. FXTAS diagnostic criteria in FMR1 premutation carriers(8).

Diagnostic Categories
Definite:	Presence of one major radiological sign plus one major clinical symptom
Probable:	Presence of either one major radiological sign plus one minor clinical symptom or has the two major clinical symptoms
Possible:	Presence of one minor radiological sign plus one major clinical symptom
Symptom Types
Radiological
Major	MRI white matter lesions in MCPs and or brain stem
Minor	MRI white matter lesions in cerebral white matter
Minor	Moderate to severe generalized atrophy
Clinical
Major	Intention tremor
Major	Gait ataxia
Minor	Parkinsonism
Minor	Moderate to severe short-term memory deficiency
Minor	Executive function deficit

MCP = middle cerebellar peduncle