The Y chromosome is the chromosome that is responsible for masculinity and biological manhood. However, researchers are beginning to understand that the y chromosome is disappearing and may one day disappear completely.
Over time, researchers have noticed that the y chromosome is shriveling. While it may not be eradicated for another 4.6 million years, when you consider that life has existed for 3.5 billion years, you see that this timing is still relevant.
Now, let’s be clear, the y chromosome hasn’t always been this way. Around 166 million years ago, the early proto-Y chromosome was the same size as the Y chromosome and still had all of the same genes. Fast forward to modern times, and this simply isn’t the case.
The X chromosome contains around 900 genes that do many jobs, not related to gender. The Y chromosome only contains around 55 genes, including noncoding DNA that doesn’t do much of anything. The good news? Many rodents have completely lost their Y chromosomes and they continue to thrive.
Still, research has also shown that the Y chromosome is fighting for its life by attempting to slow the loss. In a Danish study, they sequenced the portions of the Y chromosome from 62 men and found that their structural gene rearrangements were allowing gene amplification, which copies genes to assist in healthy sperm function.
Even with this said, the Y chromosome’s days are numbered. Many species have already phased out the y chromosome, and when this happens to us, one of two things will happen: either a new sex-determining gene will develop over time or the human race will cease to exist. The good news is that the research supports the latter.
What this could mean is that we could see a new species of human a few million years down the line. Either that, or we will be completely eradicated. Only time will tell.