Stable alteration of pre-mRNA splicing patterns by modified U7 small nuclear RNAs

Proc Natl Acad Sci U S A. 1998 Apr 28;95(9):4929-34. doi: 10.1073/pnas.95.9.4929.


In several forms of beta-thalassemia, mutations in the second intron of the beta-globin gene create aberrant 5' splice sites and activate a common cryptic 3' splice site upstream. As a result, the thalassemic beta-globin pre-mRNAs are spliced almost exclusively via the aberrant splice sites leading to a deficiency of correctly spliced beta-globin mRNA and, consequently, beta-globin. We have designed a series of vectors that express modified U7 snRNAs containing sequences antisense to either the aberrant 5' or 3' splice sites in the IVS2-705 thalassemic pre-mRNA. Transient expression of modified U7 snRNAs in a HeLa cell line stably expressing the IVS2-705 beta-globin gene restored up to 65% of correct splicing in a sequence-specific and dose-dependent manner. Cell lines that stably coexpressed IVS2-705 pre-mRNA and appropriately modified U7 snRNA exhibited up to 55% of permanent restoration of correct splicing and expression of full-length beta-globin protein. This novel approach provides a potential alternative to gene replacement therapies.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Base Sequence
  • Globins / genetics*
  • HeLa Cells
  • Humans
  • Molecular Sequence Data
  • RNA Splicing
  • RNA, Antisense
  • RNA, Messenger / metabolism*
  • RNA, Small Nuclear / genetics*
  • beta-Thalassemia / genetics


  • RNA, Antisense
  • RNA, Messenger
  • RNA, Small Nuclear
  • Globins