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Updated: Jul 14, 2026
08:06
Genome-wide Determination of Mammalian Replication Timing by DNA Content Measurement
Published on: January 19, 2017
Measuring the accuracy of genome-size multiple alignments.
1Department of Computer Science and Engineering, University of Washington, Seattle, WA 98195-2350, USA. amol.prakash@thermofisher.com
Genome Biology
|June 28, 2007
Summary
We developed a method to assess genome alignment accuracy. Applying this to human chromosome 1 revealed 9.7% of the alignment is suspicious, indicating potential misalignments in comparative genomics.
Area of Science:
- Genomics
- Bioinformatics
- Comparative Genomics
Background:
- Whole-genome alignments are crucial for understanding evolutionary relationships and gene function across species.
- Assessing the accuracy of these alignments is essential before performing downstream comparative analyses.
- Existing methods may not provide region-specific accuracy measures for large-scale alignments.
Purpose of the Study:
- To develop and validate a novel methodology for quantifying the accuracy of arbitrary regions within whole-genome alignments.
- To apply this methodology to a large-scale, multi-species alignment, specifically the UCSC Genome Browser's 17-vertebrate alignment.
- To identify and characterize potentially misaligned regions in human chromosome 1 within this alignment.
Main Methods:
- Development of a computational framework to assess alignment quality at a regional level.
- Application of the methodology to the human chromosome 1 segment of the UCSC 17-vertebrate genome alignment.
- Statistical analysis to identify regions with low alignment confidence scores.
- Validation using independent biological evidence to support identified misalignments.
Main Results:
- A new methodology for measuring the accuracy of specific regions in whole-genome alignments was successfully developed.
- Analysis of the UCSC 17-vertebrate alignment revealed that 9.7% (21 Mbp) of human chromosome 1 is flagged as suspiciously aligned.
- Independent evidence was gathered, corroborating that a significant portion of these flagged regions likely represent true sequence misalignments.
Conclusions:
- The developed methodology provides a reliable way to assess the accuracy of specific genomic regions within large-scale alignments.
- A substantial fraction of the human chromosome 1 alignment in the UCSC 17-vertebrate dataset exhibits questionable accuracy, suggesting widespread misalignments.
- These findings highlight the importance of alignment quality assessment in comparative genomics and may necessitate re-evaluation of specific genomic regions for evolutionary studies.
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