A SIMPLE AND RELIABLE METHOD FOR DETECTIO N OF R408W MUTATION IN EXON-12 OF PHENYLALANINHYDROXILASE GENE IN MOLECULAR DIAGNOSTICS OF PHENYLKETONURIA

A new method for identification of R408W mutation common in phenylketo nuria (PkU) patients in Russia and Eastern Europe is presented. The me thod is based on restriction of amplified exon 12. Amplification was a chieved by PCR and was followed by restriction with StyI endonuclease. This enzyme specifically recognized allele R408W (C-T change in the p osition 1444 of the PAH gene) but not the normal allele. The method is easily reproduced both in DNA samples and in blood spots on the blott ing paper (Gathrie cards) as well as in native cells from chorionic vi lli samples and amniocytes without preliminary DNA extraction. The met hod is very reliable and quick and has obvious advantages over other m ethods (ASO, ARMS) routinely used for identification of R408W mutation in the PKU high risk families.