After a long day on the wheel, some hamsters still don’t get enough shut-eye.

But a team of Northwestern researchers led by Prof. Joseph Takahashi has discovered a protein coded by a mutated gene in certain hamsters that makes them lose four hours in their biological clocks.

Researchers at the University of Oregon discovered the mutation more than 10 years ago, but no one has determined its protein nature until now. A normal hamster has a 24-hour biological clock, but one affected by the mutation has only a 20-hour clock.

Researchers from NU’s neurobiology and physiology department, with the help of researchers from the University of Toronto and the University of Virginia, found the enzyme that causes the hamster quirk.

“Within the scientific world, it’s pretty big because it’s a very difficult task to find a gene in a hamster,” Takahashi said.

Because so much research is conducted on mice, rats and humans, the team faced a challenge researching the uncharted gene map of hamsters, he said.

“Those genetic maps are very dense,” said Phillip Lowrey, a graduate student who worked on the team. “If you compared it to a road map, there are a lot of markers on the maps. You would see a lot of signs along the way that tell you how far you are from your destination. But in hamsters, there were none of these markers developed.”

To chart the hamster genes, the researchers identified markers that corresponded with markers in mice and humans. Then they tried to find the mutation in relation to those markers, Lowrey said.

“By doing that, we were able to hone in on the one gene,” he said.

After the team found the gene that was the possible cause of the mutation, the researchers had to clone the gene from unaffected hamsters and compare the results with mutated hamster genes.

“The good thing about this discovery is that we know with the mammalian clock, there is an enzyme definitely involved,” Lowrey said. “As a result, in the future, it may give us the opportunity to discover drug targets.”

Takahashi said that some human sleeping disorders might be caused by enzymes like the hamsters’ disorder. In that case, a treatment could be discovered to treat them.

But it’s not only the lab hamsters that have unusual sleeping patterns. Some of the researchers have odd sleeping habits of their own, Takahashi said.

“Among my grad students, I have some extreme night owls,” he said.