title: Genetic basis of the silent phenotype of serum butyrylcholinesterase in three compound heterozygotes.
abstract: Three Japanese patients showed very low butyrylcholinesterase activity in their sera and appeared to be homozygous for silent genes for butyrylcholinesterase. From DNA analysis, all three patients were compound heterozygotes: GGA(Gly) to CGA(Arg) at codon 365 (G365R) and TTC(Phe) to TCC(Ser) at codon 418 (F418S) in patient 1, G365R and CGT(Arg) to TGT(Cys) at codon 515 (R515C) in patient 2 and ACT(Thr) to CCT(Pro) at codon 250 (T250P) and AGA(Arg) to TGA(Stop) at codon 465 (R465X) in patient 3. The K-variant, GCA(Ala) to ACA(Thr) at codon 539, was also found in patients 1 and 2. Simple identification methods for all the mutations were developed and applied to family analysis and control individuals. The mutant alleles (with silent gene and K-variant) were segregated as predicted by theory in pedigrees of patients 1 and 2. Four of the mutations, F418S, R515C, T250P and R465X, were initially discovered in Japan and genetic heterogeneity among the human population for the butyrylcholinesterase gene was suggested.
authors.affiliation: Department of Laboratory Medicine, Hamamatsu University School of Medicine, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Maekawa
authors.forename: K
authors.initials: K
authors.lastname: Sudo
authors.forename: T
authors.initials: T
authors.lastname: Kanno
authors.forename: K
authors.initials: K
authors.lastname: Kotani
authors.forename: D C
authors.initials: DC
authors.lastname: Dey
authors.forename: J
authors.initials: J
authors.lastname: Ishikawa
authors.forename: M
authors.initials: M
authors.lastname: Izumi
authors.forename: K
authors.initials: K
authors.lastname: Etoh
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D002091:Butyrylcholinesterase / Q000097:blood* / Q000172:deficiency / Q000235:genetics*; D018389:Codon, Nonsense / Q000235:genetics; D018740:Genetic Heterogeneity; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D007564:Japan; D008969:Molecular Sequence Data; D010375:Pedigree; D010641:Phenotype; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D018807:Polymorphism, Single-Stranded Conformational; D017421:Sequence Analysis
chemical_list: D018389:Codon, Nonsense; D002091:Butyrylcholinesterase