A novel exon mutation in the human beta-hexosaminidase beta subunit gene affects 3' splice site selection.
Article Details
- CitationCopy to clipboard
Wakamatsu N, Kobayashi H, Miyatake T, Tsuji S
A novel exon mutation in the human beta-hexosaminidase beta subunit gene affects 3' splice site selection.
J Biol Chem. 1992 Feb 5;267(4):2406-13.
- PubMed ID
- 1531140 [ View in PubMed]
- Abstract
The molecular basis of a dramatically decreased steady state level of beta-hexosaminidase beta subunit mRNA in a patient with juvenile Sandhoff disease was investigated. Nucleotide sequence analysis of the HEXB gene coding for the beta subunit revealed two single base substitutions, one in exon 2 (A to G, a known polymorphism) and the other in exon 11 (C to T). Analysis of the beta subunit mRNA species demonstrated activation of a cryptic splice site in exon 11 as well as skipping of the exon. A transfection assay using a chimeric gene containing intron 10 flanked by cDNA sequences carrying the mutation confirmed that the single base substitution located at position 8 of exon 11 inhibits the selection of the normal 3' splice site. The results demonstrate a new type of exon mutation affecting 3' splice site selection.