A European pilot quality assessment scheme for molecular diagnosis of Huntington's disease

This paper reports a European pilot External Quality Assessment (EQA) schem e for the molecular diagnosis of Huntington's disease (HD), The European Mo lecular Genetics Quality Network (EMQN) chose HD as a relatively simple ass ay that allows a range of difficulty in terms of technical competence and i nterpretation. Fourteen centres from 12 different countries participated. T he scheme organiser provided five cases together with mock clinical informa tion. The participating laboratories were asked to complete the analyses an d return the reports in English to their normal laboratory format within a fixed period. The scheme demonstrates a level of potential misdiagnosis in molecular analysis of HD as well as a wide variety in way of reporting labo ratory results, Overall 9/146 (6.2%) of alleles fell outside the set limits , and the rate of misdiagnosis was 1/78 (1.3%). A closer estimate of diagno stic accuracy will require expansion of the scheme.