RAPID CAPILLARY-ZONE-ELECTROPHORESIS IN ISOELECTRIC HISTIDINE BUFFER - HIGH-RESOLUTION OF THE POLY-T TRACT ALLELIC VARIANTS IN INTRON-8 OF THE CFTR GENE

The poly-T tract in intron 8 of the cystic fibrosis conductance transm embrane regulator (CFTR) gene exists in three variants, 5T, 7T, and 9T . The 7T and 9T variants generate a predominantly normal transcript, w hereas the 5T variant engenders an anomalous product. The analysis of the poly-T tract is assuming increasing relevance, both to assess the implication of the CFTR gene in congenital bilateral absence of the va s deferens and to evaluate genotype-phenotype correlation in cystic fi brosis. Mapping of the poly-T tract has been performed by cumbersome a nd time-consuming methodologies. Capillary zone electrophoresis, combi ned with laser-induced fluorescence detection, was introduced for a ra pid separation of the poly-T tract amplified products. As separation b uffer, we adopted 200 mmol/L histidine (pH = pI = 7.6), and the capill ary was filled with 10% polyacrylamide, allowing separations in less t han 10 min. Capillary zone electrophoresis results were in perfect agr eement with dot-blot analysis.