Researchers fully sequence the Y chromosome for the first timeDate: August 23, 2023
Source: National Institute of Standards and Technology (NIST)
Summary: What was once the final frontier of the human genome -- the Y chromosome -- has just been mapped out in its entirety. Scientists used advanced sequencing technologies to read out the full DNA sequence of the Y chromosome -- a region of the genome that typically drives male reproductive development. The results demonstrate that this advance improves DNA sequencing accuracy for the chromosome, which could help identify certain genetic disorders and potentially uncover the genetic roots of others.
Led by the National Human Genome Research Institute (NHGRI), a team of researchers at the National Institute of Standards and Technology (NIST) and many other organizations used advanced sequencing technologies to read out the full DNA sequence of the Y chromosome -- a region of the genome that typically drives male reproductive development. The results of a study published in Nature demonstrate that this advance improves DNA sequencing accuracy for the chromosome, which could help identify certain genetic disorders and potentially uncover the genetic roots of others.
DNA sequencing isn't as simple as reading genetic material from a genome's beginning to its end. DNA gets chopped up when it is extracted from cells, plus even the best sequencing equipment can only handle relatively small bits of DNA at a time. So, researchers and clinicians rely on special software to piece together fragments of sequenced code in the correct order like a puzzle.
A reference genome is a separate, already pieced-together genome that serves as a guide, similar to the pictures on the front of puzzle boxes. And because 99.9% of our species' genetic code is shared, any human genome would closely match a reference.
Last year, a team from the Telomere-to-Telomere (T2T) consortium, which is made up of experts from dozens of organizations such as NIST, generated the most complete reference genome at the time by using new sequencing technologies to crack previously indecipherable regions of the genome. But cells used in that work did not contain the most puzzling of all, the Y chromosome.
"Chromosomes all contain sections of very repetitive DNA, but well over half of the Y chromosome is like that," said study co-author Justin Zook, who leads NIST's Genome in a Bottle (GIAB) consortium. "If you use the puzzle analogy, a lot of the Y chromosome looks like the backgrounds often do, where all the pieces look really similar."
With this new endeavor, T2T was not starting at zero as the GIAB had already gotten the ball rolling.
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Source:
https://www.sciencedaily.com/releases/2023/08/230823122524.htm
