Of Mice and Men, It’s a Fine (DNA) Line
What makes a man different from a mouse? Genetically, it is pretty hard to tell, according to researchers.
An initial comparison of one mouse chromosome to a human chromosome shows the genes they carry are highly similar, a team at the genome company Celera Genomics reports in today’s issue of the journal Science.
Richard Mural and a team of colleagues at Celera compared chromosome 16 in the mouse to human chromosome 21, which it closely resembles.
“To me, the thing that I found the most interesting is just how similar the mouse and the human are in respect to genes, and gene content and DNA sequences,” said Neal Copeland, an expert in genetics and genomics at the National Cancer Institute.
The Celera researchers found that mice have about 10% less DNA than humans, mostly because the human genome has a great deal of repetitive sequences, once called “junk DNA.”
Celera is publishing the information about chromosome 16 in the public GenBank, but holding back the rest of the mouse genome data for paying clients. They found what look like 731 genes on the mouse chromosome.
“Fourteen genes have no known human homologs [counterparts], whereas 21 human genes in the compared regions are unique to humans,” Copeland and colleagues Nancy Jenkins and Stephen O’Brien at the National Cancer Institute said in a commentary.
The 14 genes may be unique to mice, or their human counterparts may lie elsewhere, Mural’s team said. Based on this, it could be predicted that about 2% of mouse genes are unique to mice, and about 2.9% are unique to humans, the researchers said.
