Transposon silencing

Transposon silencing is a form of transcriptional gene silencing targeting transposons. Transcriptional gene silencing is a product of histone modifications that prevent the transcription of that area of DNA. Transcriptional silencing of transposons is crucial to the maintenance of a genome. The “jumping” of transposons generates genomic instability and can cause extremely deleterious mutations. Transposable element insertions have been linked to many diseases including hemophilia, severe combined immunodeficiency, and predisposition to cancer. The silencing of transposons is therefore extremely critical in the germline in order to stop transposon mutations from developing and being passed on to the next generation. Additionally, these epigenetic defenses against transposons can be heritable. Studies in Drosophila, Arabidopsis thaliana, and mice all indicate that small interfering RNAs are responsible for transposon silencing. In animals, these siRNAS and piRNAs are most active in the gonads.