Detection of prion protein gene mutation in a pedigree with fatal familial insomnia from Guangdong province and the clinical manifestations of the disease

Abstract

Objective To investigate the clinical features fatal familial insomnia （FFI） and detection of the prion protein （PRNP） gene mutation in a family with FFI from Guangdong province.Methods The clinical features were analyzed in 2 patients from the family with FFI. The PRNP gene mutation was detected by using PCR and DNA sequence analysis in the proband. Results The main symptoms of the proband were characterized by progressive sleep impairment, behavior and cognitive dysfunctions; myoclonus was appeared in the late period of the disease and the whole durations of the disease were 9 months. The elder brother of the proband had the similar clinical manifestations with the duration of 11 months. The prion protein D178N mutation and also homozygous for Met in the 129 codon were found in the proband. Conclusion The typical clinical manifestations can help the diagnosis of FFI and the technique of PRNP gene mutation detection could provide a definite diagnosis. Key words: Fatal familial insomnia; Signs and symptoms; PRNP gene; Gene mutation