| Passage Frozen |
9 |
| |
| IDENTIFICATION OF SPECIES OF ORIGIN |
Species of Origin Confirmed by Nucleoside Phosphorylase and Glucose-6-Phosphate Dehydrogenase Isoenzyme Electrophoresis and by Chromosome Analysis |
| |
| Gene |
CFTR |
| Chromosomal Location |
7q31.2 |
| Allelic Variant 1 |
602421.0001; CYSTIC FIBROSIS |
| Identified Mutation |
PHE508DEL; Deletion of codon 508 (CTT) in exon 10 leads to deletion of phenylalanine-508 (delta-F508). |
| |
| Gene |
CFTR |
| Chromosomal Location |
7q31.2 |
| Allelic Variant 2 |
602421.0082; CYSTIC FIBROSIS |
| Identified Mutation |
GLU92TER; In each of 4 German patients with cystic fibrosis, Will et al. [J. Clin. Invest. 93: 1852-1859 (1994)] found a G-to-T transversion that affected the first base of exon 4 and created a termination codon glu92-to-ter. Lymphocyte RNA of patients heterozygous for the E92X mutation were found to contain the wildtype sequence and a differentially spliced isoform lacking exon 4. On the other hand, RNA derived from nasal epithelial cells of these patients showed a third fragment of longer length. Sequencing revealed the presence of E92X and an additional 183-bp fragment, inserted between exons 3 and 4. The 183-bp sequence was mapped to intron 3 of the CFTR gene. It was flanked by acceptor and donor splice sites. Will et al. [J. Clin. Invest. 93: 1852-1859 (1994)] concluded that the 183-bp fragment in intron 3 is a cryptic CFTR exon that can be activated in epithelial cells by the presence of the E92X mutation. E92X abolishes correctly spliced CFTR mRNA and leads to severe cystic fibrosis. |