The Human Genome Project was declared complete in 2003 when it had mapped 92% of genes. The rest, however, remained a mystery for nearly two decades due to technological limitations. Now, scientists have finished sequencing the other 8%, and the human genome has finally been fully sequenced.
Fully Sequenced Human Genome Project
The Human Genome Project is fully sequenced now. Almost 100 scientists from the Telomere-to-Telomere (T2T) Consortium collaborated on the project to map the entire human genome. The additional 8% that was sequenced accounts for 400 million new letters added to the existing sequenced DNA—enough for an entire chromosome.
As detailed in the research, which was published in six papers in the journal Science on March 31, the team used two DNA sequencing methods: the “ultralong” Oxford Nanopore method, which sequences up to one million DNA letters with a 5% error rate, and the PacBio HiFi sequencing method, which reads 20,000 letters at a time but has a far smaller (0.01%) error rate.
Results of the Project
While the researchers used the former to span extended lengths of repeated DNA, they used the latter to discern how some lengths that looked like exact replications were actually subtly different.
The resulting fully sequenced genome is now a resource that other scientists can use to springboard their own research, though it only represents a single example. Further study by the T2T Consortium along with the Human Pangenome Reference Consortium will build out more genome examples, called haplotypes, from a diverse range of samples, according to the published research. This is another big step in enabling humans to sequence their individual genomes, which could drop in the accessibility and cost to become a routine medical test that could run you under $1,000, study author Adam Phillippy, a genomicist with the National Institutes of Health, told CNN. In the meantime, scientists will be able to use the completed Human genome to investigate whether genetic variations are linked to particular cancers. Even with this accomplishment, more work and deeper understanding lie ahead.