EDITING OF HUMAN ALPHA-GALACTOSIDASE RNA RESULTING IN A PYRIMIDINE TOPURINE CONVERSION

During a study of the gene coding for a-galactosidase (EC 3.2.1.22), t he lysosomal enzyme deficient in Fabry's disease, RT-PCR amplification of a-galactosidase mRNAs obtained from three different tissues isolat ed from males revealed a substantial number of clones with a U to A co nversion at the nucleotide position 1187, Such a modification of the c oding sequence would result in an amino acid substitution in the C-ter minal region (Phe396Tyr) of the enzyme, Neither PCR analysis of the ge nomic sequence nor the RT-PCR amplification of RNA obtained by in vitr o transcription of the wild-type cDNA showed this change in the sequen ce, Multiple genes, pseudogenes or allelic variants were excluded, Hen ce, we propose RNA editing as a mechanism responsible for this base ch ange in the cr-galactosidase RNA.