3 DIFFERENT POINT MUTATIONS IN THE BUTYRYLCHOLINESTERASE GENE OF 3 JAPANESE SUBJECTS WITH A SILENT PHENOTYPE - POSSIBLE JAPANESE TYPE ALLELES

Objective: To investigate genetic mutations in three Japanese subjects homozygous for silent butyrylcholinesterase mutations. Methods and Re sults: One of them was compound heterozygous for two mutations; GGA(Gl y) to CGA(Arg) at codon 365 (G365R) and CAA(Gln) to TAA(Ter) at codon 119 (q119X). The other two subjects were homozygous for different miss ense mutations: CGT(Arg) to TGT(Cys) at codon 515 (R515C) and G365R, r espectively. Simple identification methods for all of the mutations we re developed and applied for family analysis and to control individual s. Two mutations, G365R and R515C, have been reported in the Japanese population, while the nonsense mutation Q119X was discovered in the pr esent study. Genetic heterogeneity between human populations with rega rd to the butyrylcholinesterase gene was suggested. Conclusions: Among the three mutations found in this investigation, one was novel, and n one of these mutations have been reported outside Japan.