[Analysis of fragile X mental retardation 1 gene premutation in multiple system atrophy patients].

Objective: To investigate whether Chinese multiple system atrophy (MSA) patients have premutation of fragile X mental retardation 1 gene(FMR1).

Methods: FMR1 CGG repeats were analyzed in 157 MSA patients by polymerase chain reaction, agarose gel electrophoresis and capillary electrophoresis. The patients were collected from Movement Disorder & Neurogenetics Research Center of China-Japan friendship hospital. There were 83 male cases and 74 female cases, including 51 MSA-C patients, 12 MSA-P patients and 94 MSA-P+C patients.

Results: No FMR1 CGG repeat premutation was detected in 157 MSA patients. The repeats ranged from 11-49, most common allele was 22. A MSA-C case carried 35/49 alleles did not have middle cerebellar peduncles(MCP) sign which was necessary for the diagnosis of fragile X associated tremor ataxia syndrome(FXTAS).

Conclusion: The FMR1 premutation in Chinese MSA patients might be very rare.