“Having this complete information will allow us to better understand how we form as an individual organism and how we differ not only from other people but also from other species,” said Evan Eichler, a researcher at the Howard Hughes Medical Institute at the University of Washington and lead researcher. . , he said on Thursday. The new research inserts 400 million letters into the DNA that had previously followed – the value of an entire chromosome. The complete genome will allow scientists to analyze how DNA differs between humans and whether these genetic variants play a role in the disease. Until now, it was not clear what encoded these unknown genes. “These genes are proving to be incredibly important for adaptation,” Eichler said. “They contain immune response genes that help us adapt and survive infections and infections and viruses. “They contain genes that are… very important in predicting the response to drugs.” Eichler also said that some of the genes recently discovered are responsible for making the human brain larger than that of other primates, providing an insight into what makes humans unique. This remaining 8% of the human genome had misled scientists for years because of its complexity. First, it contained DNA regions with multiple replications, which made it difficult to assemble the DNA in the correct order using previous sequencing methods. The researchers relied on two DNA sequencing technologies that have emerged in the last decade to accomplish this task: Oxford’s Nanopore DNA sequencing method, which can sequence up to 1 million DNA letters simultaneously but with some errors, and DNA sequencing PacBio HiFi method, which can read 20,000 letters with 99.9% accuracy. DNA sequencing is like solving a puzzle, Eichler said. Scientists must first break the DNA into smaller pieces and then use sequencing machines to put it together in the correct order. Previous sequencing tools could only sequence small portions of DNA at a time. With a 10,000-piece puzzle, it is difficult to properly arrange small puzzle pieces when they look like, such as sequencing small pieces of repeating DNA. But with a 500-piece puzzle, it’s much easier to arrange larger pieces – or, in this case, larger pieces of DNA. Typical human cells contain two sets of DNA, a parent copy and a parent copy, but this group used DNA from a group of cells called a complete hydroform molecule, which contains a copy of the parent DNA set. A complete watery nevus is a rare complication of a pregnancy caused by abnormal growth of placental cells. This approach simplifies the genome so that scientists need only one set of sequences instead of two sets of DNA. Because the research team used a double strand of DNA, the scientists were unable to determine the Y chromosome sequence initially. According to study lead author Adam Phillippy, the team was able to determine the Y chromosome sequence using a different set of cells. A complete set of 24 sequenced chromosomes is available in the genome browser of the University of Santa Cruz. Decoding this sequence without gaps is costly. Phillippy, who also heads the Department of Genetic Informatics at the National Human Genome Research Institute, said the project alone cost a few million dollars or more. But that’s a fraction of the $ 450 million it owed the Human Genome Project to make its final sequel in 2003. And with new technology, the sequence is only getting cheaper. At present, their own genome is still very costly and time consuming to sequence. But research is under way that uses this genome to determine if certain genetic differences are linked to specific cancers. Knowing genetics The variations could also allow doctors to better tailor treatments, said Michael Schatz, another team researcher and professor of computer science and biology at Johns Hopkins University. Phillippy said he hopes that within the next 10 years, sequencing the genomes of individuals can become a standard medical examination that costs less than $ 1,000. His team continues to work towards this goal. Charles Rotimi, scientific director of the National Institute for Human Genome Research, said in a statement that this scientific achievement “brings us closer to personalized medicine for all of humanity.” Rotimi did not participate in the investigation. Correction: An earlier version of this story mistyped Evan Eichler’s name.
