In a series of papers published in Science, the T2T consortium reported how it managed to cover almost all but five missing points, leaving only 10 million and the Y chromosome vaguely understood. Following the release of the papers, the consortium scientists revealed on Twitter that they understood the correct assembly for the Y chromosome and that they would publish another document with the latest results. Evan Eichler, head of research at the University of Washington, likened the sequence of a DNA to the solution of a puzzle. Scientists have to break DNA into small pieces and then use sequencing machines to put them together. Older tools could only sequence small pieces of DNA at a time, so it’s like solving these pointless hard puzzles with tens of thousands of repetitive, almost identical pieces. Newer tools can sequence larger sections of DNA, making it much easier to find the right sequence. To make the process less complicated, the team used a cell line from a failed pregnancy called a mole, where the sperm enters an egg that does not have its own set of chromosomes. This means that the team had to follow only one DNA set instead of two. They then used a technique called Oxford Nanopore to complete sets of centromere, which are dense knobs in the middle of the chromosomes. However, Oxford Nanopore has a relatively high error rate, making it less than ideal for sequencing DNA repeats. For these areas, the team used another technique called PacBio HiFi, which can follow smaller incisions with 99.9% accuracy. Eichler said previously unknown genes include genes for the immune response that help us survive infections and viruses, genes that help predict a person’s response to drugs, and genes that are responsible for making the human brain bigger than other primates. . “Having this complete information will allow us to better understand how we are formed as an individual organism and how we differ not only from other people but also from other species,” Eichler said. The consortium project cost several million dollars to achieve, but the sequence is getting cheaper with new technologies. Adam Phillippy, another lead author of the study, said the hope is that the single-genome sequence will cost just $ 1,000 over the next decade. This could make the DNA sequence part of routine medical examinations, which could help doctors create personalized treatments for individuals.
