When people think about the function if the Y Chromosome they think that it is only used to determine gender in organisms. The Y chromosome also includes the genes that are required for the genome to function properly. The reason that the Y chromosome is so much smaller that its counterpart, the X chromosome, is that it has shed hundreds of genes over time.
So why hasn't the Y chromosome lost all of its genes, maybe even become extinct, by now? No one know for sure but a recent study in 2012, conducted by Daniel W. Bellott and David C. Page of the Whitehead Institute in Cambridge, Mass., found that humans have the same number of Y chromosomes as the rhesus monkey. This suggests that for the last 25 million years the Y chromosome stabilized. Scientist figured that it was 25 million years ago because that was the last time that the rhesus and humans had a common ancestor. Since the Y chromosome is so small it is extremely difficult to decode it. However this has not stopped Dr. Page and her group from decoding the DNA sequence of the Y chromosome in eight mammals.
Other research has be done on the Y chromosome by, Diego Cortez and Henrik Kaessmann of the University of Lausanne in Switzerland. Together they realized that they could find the Y chromosome's genes by simply comparing the X and Y DNA of other species and assuming that if the genetic sequences did not match to the X must come from the Y.
Go to the link below to find out more:
http://www.nytimes.com/2014/04/24/science/researchers-see-new-importance-for-y-chromosome.html?ref=science&_r=0
NOS Themes:
Science is based on evidence- the y chromosome determines the gender.
Importance of repeatability- they have done multiple trials on their research.
Role of motivation and curiosity- the scientists are interested in finding out more about the y chromosome.
That is so interesting! In another article (http://www.huffingtonpost.com/2014/04/26/y-chromosome-evolution-study_n_5201050.html), I read how the Y chromosome has shed its genes over time until only 3 percent of it remains now. I also found it surprising that the Y chromosome is active in more than just deciding gender. Researchers have found that the Y chromosome causes differences between men and women for certain diseases. An example is that males are more likely to acquire autism while women more commonly develop autoimmune diseases than men.
ReplyDeleteThis is super interesting! I found an interesting article that relates to the y chromosome. It's about artificially creating male mice without the y chromosome. Basically they activate a single gene, called SOX3, in the developing fetus. SOX3 is important for brain development, but has not previously been shown to be capable of triggering the male pathway. The SOX3 is able to create male mice, but they are sterile.
ReplyDeleteFor more information: http://www.sciencedaily.com/releases/2010/12/101222121513.htm