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Transposable elements in disease-associated cryptic exons
1Division of Human Genetics, University of Southampton School of Medicine, MP808, Tremona Road, Southampton SO16 6YD, UK. igvo@soton.ac.uk
Human Genetics
|October 14, 2009
Summary
Transposable elements (TEs) contribute to cryptic exons in over half of genetic diseases studied. Short interspersed nuclear elements (SINEs), particularly Alus and MIRs, are frequently involved in activating these disease-associated exons.
Area of Science:
- Genomics
- Molecular Biology
- Genetic Diseases
Background:
- Transposable elements (TEs) constitute a significant portion of the human genome.
- The role of TEs in the activation of cryptic exons leading to genetic diseases remains largely unexplored.
Purpose of the Study:
- To investigate the contribution of TEs to the formation of cryptic exons in human genetic diseases.
- To identify specific types of TEs involved and the mechanisms of their exonization.
Main Methods:
- Comprehensive survey of 78 mutation-induced cryptic exons in 51 disease genes.
- Analysis of TE presence, type (Alus, MIRs, SINEs), and location within cryptic exons.
- Evaluation of splice site characteristics and evolutionary conservation of splicing signals.
Main Results:
- Transposable elements were found in 51% of the surveyed cryptic exons.
- Short interspersed nuclear elements (SINEs), including Alus and MIRs, were the predominant TE types.
- Phylogenetically conserved changes enhanced splicing signals, facilitating the inclusion of intronic TEs as cryptic exons.
Conclusions:
- TEs are significant contributors to cryptic exon formation and genetic disease.
- Specific features of MIRs and Alus facilitate their pathogenic exonization.
- Understanding these mechanisms aids in detecting intronic mutations and developing predictive tools for TE-driven cryptic exon activation.
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