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06:40
G2-seq: A High Throughput Sequencing-based Technique for Identifying Late Replicating Regions of the Genome
Published on: March 22, 2018
Building the sequence map of the human pan-genome
Ruiqiang Li1, Yingrui Li, Hancheng Zheng
1BGI-Shenzhen, Shenzhen 518083, China.
Nature Biotechnology
|December 10, 2009
Summary
Scientists assembled Asian and African genomes to build a human pan-genome. They discovered millions of novel DNA sequences, revealing genetic diversity and migration patterns, crucial for a complete human genome understanding.
Area of Science:
- Genomics
- Human Genetics
- Bioinformatics
Background:
- The current human reference genome is incomplete, primarily based on a single individual.
- Understanding human genetic diversity requires a more comprehensive representation of the genome.
Purpose of the Study:
- To construct a more complete human pan-genome by integrating de novo assemblies of diverse human genomes.
- To identify and characterize novel DNA sequences absent from the existing reference genome.
Main Methods:
- De novo assembly of Asian and African genomes.
- Comparison of novel sequences against the NCBI human reference genome and available human DNA sequence data.
- Polymerase chain reaction (PCR) validation using the human genome diversity cell line panel.
- Cross-species conservation analysis of predicted genes within novel sequences.
Main Results:
- Approximately 5 Mb of novel sequences were identified in each of the Asian and African genome assemblies.
- Most novel sequences were found to be individual or population-specific.
- The distribution of novel sequences aligns with patterns of known human migration.
- Predicted genes within novel sequences show cross-species conservation, indicating potential functionality.
- An estimated 19-40 Mb of novel sequence is expected in a complete human pan-genome.
Conclusions:
- The existing human reference genome significantly underestimates human genetic variation.
- De novo assembly of diverse genomes is essential for capturing novel sequences and building a comprehensive human pan-genome.
- The identified novel sequences contribute substantially to human genetic diversity and hold functional significance.
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