The UK National External Quality Assessment Scheme (UK NEQAS) for molecular genetic testing in haemophilia

Abstract

Molecular genetic analysis of families with haemophilia and other inherited bleeding disorders is now a common laboratory investigation. In contrast to phenotypic testing in which strict quality control is adhered to, in haemophilia molecular genetic testing there has been a lack of any external quality assurance schemes. In 1998 the UK National External Quality Assessment Scheme (UK NEQAS) established a pilot quality assurance scheme for molecular genetic testing in haemophilia. Results from three initial surveys highlighted problems with the quality of samples when used to screen for the intron 22 inversion within the F8 gene. The scheme was re-launched in 2003, and since that time there have been five exercises involving whole blood or immortalised cell line DNA. The results together with an overall summary of the exercise are subsequently returned to participants. Exercises to date have focused exclusively on haemophilia A and QA, material has included screening for the intron 1 and intron 22 inversions as well as sequence analysis. A paper exercise circulated in 2003 highlighted problems with the format of reports and, following feedback to participants, only a single error has been made in the subsequent four exercises. Participating laboratories now receive QA material every six months. Immortalised cell line material was introduced in 2005 and was shown to perform well. This will allow expansion of the scheme and a reduction in the dependence on blood donation.