Related Experiment Video
Updated: May 27, 2026
11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
Pathogenic orphan transduction created by a nonreference LINE-1 retrotransposon.
Szilvia Solyom1, Adam D Ewing, Dustin C Hancks
1McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Human Mutation
|November 19, 2011
Summary
A novel cause of Duchenne muscular dystrophy was identified as a Long INterspersed Element-1 (LINE-1) retrotransposon insertion. This study reveals LINE-1 mediated 3' transduction as the first example of LINE-1-induced human disease.
Area of Science:
- Genomics
- Molecular Biology
- Human Genetics
Background:
- Long INterspersed Element-1 (LINE-1) retrotransposons are mobile genetic elements comprising 17% of the human genome.
- LINE-1 elements propagate via a "copy and paste" mechanism involving an RNA intermediate, posing a risk for insertional mutagenesis.
- Retrotransposition-mediated insertion of novel transcripts has recently emerged as a cause of genetic diseases.
Observation:
- A Japanese male with Duchenne muscular dystrophy was found to have an insertion in the dystrophin gene.
- The inserted sequence was initially presumed to originate from a single-copy, noncoding RNA transcribed from chromosome 11q22.3.
- This study identified a full-length, active LINE-1 element in the proband and maternal genome at chromosome 11q22.3, upstream of the insertion site.
Findings:
- The identified LINE-1 element is highly active in cell culture assays.
- LINE-1 insertions frequently result in the transduction of adjacent genomic sequences (3' transduction).
- The mutagenic insertion is explained by a LINE-1-mediated 3' transduction with significant 5' truncation.
Implications:
- This research presents the first documented case of human disease caused by LINE-1-induced "orphan" 3' transduction.
- Understanding LINE-1 retrotransposition mechanisms is crucial for diagnosing and potentially treating genetic disorders.
- This finding highlights the significant role of mobile genetic elements in human health and disease.
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