title: Interlaboratory study of the proficiency of cholinesterase phenotyping.
abstract: We report the results of a proficiency survey into the accuracy of cholinesterase (EC 3.1.1.8) phenotyping undertaken by 12 laboratories over a three-year period, during which 21 samples of nine different genotypes were analyzed. Specimens from patients who were homozygous for the atypical variant AA or from UA and AF heterozygotes were identified without difficulty, but the less-well-recognized combinations AJ and AK were detected by only two and three laboratories, respectively. Some degree of difficulty was also experienced in differentiating among UU, UF, and FS specimens. Clinically significant ascription errors occurred on 11 occasions. We recommend that detailed studies of cholinesterase status be undertaken only by laboratories experienced in the assay, those likely to be able to produce accurate results and offer appropriate advice.
mesh_terms: D002802:Cholinesterases / Q000097:blood / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008722:Methods; D010641:Phenotype
chemical_list: D002802:Cholinesterases