2023-09-02 14:00:00
The secrets of the Y chromosome are revealed. The 23 pairs that every human wears have been extensively studied by scientists. But the Y chromosome, which only men have, was still poorly understood. Science had failed to analyze more than half of his sequence. But a team of a hundred scientists managed to decode it in its entirety. In the review Naturethese researchers reveal the importance of this particular chromosome in reproduction.
Y chromosome: why is it so difficult to decipher?
“All chromosomes have repetitive sectors, but the Y chromosome is unusually repetitive, making its sequence particularly difficult to complete, explain the authors in their study. Gathering sequencing data is like trying to read a long book cut into strips If all lines in the book are unique, it is easier to determine the order they go in. However, if the same sentence is repeated thousands or millions of times, the original order of the strips is much less clear. .”
This group of scientists used new DNA sequencing techniques and computer tools to successfully decipher these millions of repeats. “We didn’t know exactly what made up the missing sequence, warns Adam Phillippy, leader of this consortium. It might have been very chaotic, but instead, almost half of the chromosome is made up of alternating blocks of two repeating sequences. called satellite DNA.”
What is the role of the Y chromosome?
This complete sequencing also makes it possible to understand the characteristics of each sector of this chromosome. One of them is called azoospermia factor region, it contains several genes involved in sperm production. Thanks to recent discoveries, researchers have been able to study inverted repeats, also called palindromes, in this area. “This structure is very important because these palindromes can sometimes create DNA loops, specifies Arang Rhie, co-author. Sometimes these loops are accidentally cut and create deletions in the genome.” However, deletions in the region of the azoospermia factor disrupt sperm production, so these palindromes might influence fertility. The consortium’s work will provide a better understanding of their impact on sperm production. But they also succeeded in decoding a gene called TSPY, also linked to sperm production: they discovered that individuals have between 10 and 40 copies of this gene, which might also improve understanding of male fertility.
Y chromosome: what will these discoveries on the genome allow?
“When you discover variations you’ve never seen before, the hope is always that these genomic variants will become important in understanding human health.“, believes Dr. Adam Phillippy. According to him, this work might lead to the development of new, more effective diagnostic tools. Ultimately, the discoveries will potentially contribute to better management of infertility. According to theWorld Health Organizationit affects 186 million people worldwide.
1693709023
#decoding #chromosome #important
