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Alu elements: an intrinsic source of human genome instability
Catherine Ade1, Astrid M Roy-Engel, Prescott L Deininger
1Tulane University, Department of Epidemiology, School of Public Health and Tropical Medicine, Tulane Cancer Center, Consortium of Mobile Elements at Tulane, United States.
Current Opinion in Virology
|October 2, 2013
Summary
Alu elements, abundant in the human genome, are active retrotransposons contributing to genetic disease and diversity. Their activity causes genetic disorders through insertional mutagenesis and nonallelic homologous recombination.
Area of Science:
- Genomics
- Molecular Biology
- Human Genetics
Background:
- Alu elements are abundant, short interspersed repetitive sequences in the human genome, totaling over one million copies.
- These elements amplify via an RNA intermediate, representing a significant portion of the human genome's repetitive DNA.
- Germline activity of Alu elements is notably high among human retrotransposons.
Purpose of the Study:
- To elucidate the mechanisms by which Alu elements contribute to genetic disease.
- To highlight the role of Alu elements in human genetic diversity.
- To understand the impact of Alu retrotransposon activity on the human genome.
Main Methods:
- Analysis of Alu element distribution and activity in the human genome.
- Investigating insertional mutagenesis events caused by Alu elements.
- Examining the role of Alu sequences in nonallelic homologous recombination (NAHR).
Main Results:
- Alu elements significantly contribute to genetic disease through two primary mechanisms.
- Insertional mutagenesis by active Alu copies leads to genetic disorders.
- Alu elements act as a major source of repetitive sequences driving NAHR, causing deletions and duplications.
Conclusions:
- Alu retrotransposon activity is a key factor in human genetic disease pathogenesis.
- Alu elements are crucial drivers of genetic variation and population diversity.
- Understanding Alu-mediated genetic alterations is vital for diagnosing and potentially treating genetic disorders.
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