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Updated: Jul 1, 2026
08:31
Isolation and Genome Analysis of Single Virions using 'Single Virus Genomics'
Published on: May 26, 2013
Analysis of singleton ORFans in fully sequenced microbial genomes.
1Department of Chemistry, Ben Gurion University, Beer-Sheva, Israel.
Proteins
|October 1, 2003
Summary
Singleton sequence orphan open reading frames (ORFans) are growing in number but diminishing as a percentage of all sequences. Future research should focus on longer ORFans to understand their evolutionary origins and functions.
Area of Science:
- Genomics
- Bioinformatics
- Evolutionary Biology
Background:
- Singleton sequence orphan open reading frames (ORFans) lack detectable similarity to known sequences.
- ORFans present challenges for bioinformatics analysis and understanding evolutionary processes.
Purpose of the Study:
- To conduct the first systematic analysis of singleton ORFans in microbial genomes.
- To investigate the trends in ORFan abundance and characteristics.
- To propose new avenues for ORFan research.
Main Methods:
- Analysis of singleton ORFans within the first 60 fully sequenced microbial genomes.
- Quantification of ORFan numbers and their proportion relative to all sequences.
- Characterization of ORFan length distribution.
Main Results:
- The number of ORFans is increasing, totaling 23,634 sequences.
- ORFans constitute approximately 14% of all sequences, a diminishing fraction.
- Short ORFans (≤61%) are abundant, potentially due to artifacts, while longer ORFans may decrease with more genomic data.
Conclusions:
- The growing number of ORFans suggests an intrinsic, not fully understood, property of genetic material.
- Further research should prioritize longer ORFans, including ORFan modules, paralogous ORFans, and orthologous ORFans.
- Understanding protein diversity necessitates including ORFans in computational and experimental studies.
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