title: External quality assurance of DNA testing for thrombophilia mutations.
abstract: Because of the potential implications of results of genetic analyses of thrombophilic mutations, laboratories must undertake stringent internal quality control measures and participate in external quality assurance (QA) programs. A small number of external QA surveys of thrombophilic defects have been conducted across a large number of molecular laboratories and generally have indicated favorable levels of correct responses. The Royal College of Pathologists of Australasia QA program has conducted external QA testing of factor V Leiden G1691 A, prothrombin G20210A, and MTHFR C677T gene mutations for the past 5 years, including 133 DNA samples in 10 multilaboratory surveys. Of 3,799 responses, the overall success rate was 98.63%; the poorest individual sample result was 15% incorrect for a homozygous factor V Leiden sample. Success rates in identifying specific mutations were 98.13% for factor V Leiden, 98.84% for prothrombin G20210A, and 99.3% for the MTHFR C677T mutation. Among responding laboratories, 51% (20/39) made at least 1 error; 3 of 39 laboratories were responsible for 46% of all errors (24/52). Although encouraging, these data underscore the need for ongoing participation of molecular diagnostic laboratories in external QA programs to ensure the provision of quality genetic testing services.
authors.affiliation: Department of Haematology, Institute of Clinical Pathology and Medical Research, Westmead Hospital, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Hertzberg
authors.forename: Sue
authors.initials: S
authors.lastname: Neville
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Favaloro
authors.forename: David
authors.initials: D
authors.lastname: McDonald
mesh_terms: D044362:Australasia; D019411:Clinical Laboratory Techniques; D004247:DNA / Q000032:analysis*; D020022:Genetic Predisposition to Disease; D033142:Genetic Services; D006801:Humans; D007753:Laboratories; D008967:Molecular Biology / Q000592:standards*; D009154:Mutation; D011785:Quality Assurance, Health Care; D012955:Societies, Medical; D019851:Thrombophilia / Q000235:genetics*
chemical_list: D004247:DNA