NEW YORK (GenomeWeb) – Two ongoing efforts to produce new human genome assemblies are combining ultra-long nanopore reads with other types of sequencing and mapping data to generate gapless or near-gapless assemblies that can serve as reference genomes for future studies.
The Telomere-to-Telomere (T2T) consortium, led by researchers at the National Institutes of Health and the University of California, Santa Cruz, focuses on the first gapless assembly of a human genome, finishing each chromosome from one end to the other. Meanwhile, another effort, involving many of the same members as the consortium, is exploring high-throughput sequencing and assembly methods for a pan-genome reference project that aims to generate hundreds of new human genome assemblies.
At the Advances in Genome Biology and Technology conference in Marco Island, Florida, last month, Adam Phillippy, a bioinformatician in the intramural research program at the National Human Genome Research Institute, presented first results from the T2T consortium — a gapless assembly of the human X chromosome and a human genome assembly, from Oxford Nanopore and PacBio data, that is more continuous than the current GRCh38human reference genome.
Phillippy and Karen Miga, an assistant research scientist in David Haussler’s laboratory at UCSC and a satellite DNA expert, explained in an interview that the T2T consortium, which they jointly coordinate, resulted from the realization that the current human reference genome, which has hundreds of unresolved regions and gaps, leaves out important areas of the genome that play a role in disease and other processes. “All of these regions that we now know are not junk DNA but are functional regions were left off the map” Miga said. [Read More…]