A number of posts have been making the rounds on social media platforms such as X and TikTok claiming that the male Y chromosome is disappearing. Some posts even claim that this signals the impending end of male offspring in the future. These posts have garnered extremely high views – with one post having over 7 million views
.We looked further for the claim’s original source material and found a number of articles posted on small news platforms starting from 24th August that repeat the same content alongside eye-catching headlines such as “New study suggests a sex gene war,” “Is this the end of men?” or “World where only girls are born.”
These articles all appear to be based on an article published on 23rd August on the independent platform Science Alert, which is a platform for science-related news and commentary pieces. The article is a republication of a piece written by Genetics Professor Jenny Graves originally written for The Conversation in 2022.
The X and Y chromosomes (known as sex chromosomes) are present in all humans (and many mammals) and contain genes which determine biological sex. Typically, women have two XX chromosomes and men have XY chromosomes. The Y chromosome contains the SRY gene, which has the key function of triggering development of male reproductive tissues. If, as the claim suggests, the Y chromosome is “shrinking” or “vanishing,” this could lead to the loss of the key SRY gene, and subsequently prevent male births.
However, although many subsequent posts and articles based on Professor Graves’ article allude to a new study or recently published research, we were unable to find any new published work containing a direct conclusion about the disappearing Y chromosome in humans – neither does the original piece actually suggest that such a study exists.
Instead, Graves discusses how the Y chromosome has been losing active genes over the course of the evolutionary process. Some researchers (including herself) believe that this loss will continue over the next 11 million years – eventually resulting in the demise of the human Y chromosome. This is a theory she has written extensively about since 1995 although, as she notes, it has been debated by others in the same field.
While Graves’ headline includes the phrase “a new sex gene may be the future of men,” it does so in the context of exploratory research carried out on rodents whose Y chromosomes have disappeared. Research from 2022 (the latest study reference by Graves throughout the article) suggests that new sex differentiation genes in Okinawan spiny rats without the Y chromosome had developed naturally to fulfil its function. This, Graves theorises, introduces the possibility that humans could eventually evolve to do the same. However, there is not definitive or clear research that would allow scientists to make any definitive conclusions.
In summary, the “disappearing Y chromosome” refers to the observable and gradual loss of genes within the Y chromosome, although the rate and potential outcomes of this shrinkage is still without firm consensus within genetics research. The claim sprung from an article by a genetics professor and was reported on by non-science-based news platforms before going viral on social media.
Therefore, while the core claim that the Y chromosome is disappearing is not false, the context of this disappearance taking at least “several million years”, and the general lack of definitive consensus has not made it into the headlines. Therefore, we give social media posts claiming a new study has shown that the male Y chromosome is on the cusp of disappearing a rating of mostly false.
While the information and research we used to conduct this fact-check was not difficult to find and has been a part of genetics research for decades, it is hard to parse and understand.
As a result, this claim is an interesting example of how article writers can fail to accurately report on scientific news and commentary, resulting in a chain of less and less accurate headlines. For instance, failing to recognise that the recent Science Alert article was a republication from 2022 – mis-reporting a “new study” when no such thing exists. And, presenting technically true facts in isolation as part of their headlines without key context.
Despite some of these articles eventually mentioning the million-year time frame mentioned by Professor Graves, their headlines were clipped and re-shared on social media, which further fuelled the spread of misinformation. This case highlights the importance of scientific reporting – particularly when it comes to detailed nuances and context that are less eye-catching, but much more accurate.
