Scientists Identify Genetic Difference Between Early Risers And Late Sleepers

#1

http://www.iflscience.com/health-and-me ... e-sleepers

Do you prefer getting up at dawn, or staying awake to the small hours? Your answer to this probably depends on your age, but as is becoming increasingly clear, it also depends on your genes. Being an early riser or a late nighter has been seen to run in families and shows a strong genetic link. And now, researchers have started to unravel the underlying causes that make you either a “lark” or an “owl.”

The study, published in the journal Frontiers in Neurology, used fruit flies to look into the genetic variations that could play a role in determining whether an individual falls into either of these distinct categories. These model organisms have a very similar ‘genetic clock’ to humans, so the researchers think that the genes that control it in them may serve a similar function in us. After scouring their genomes, they were able to identify close to 80 genes linked to the differences in behavior.

“Most people find that their performance is at peak at specific times of day,” explained Dr. Eran Tauber, one of the co-authors. “The impact of this preference on health and behavior is well documented, but the molecular basis is largely unknown.”

The team of researchers from the University of Leicester identified the two differences in the flies' behavioral preference, or chronotype, by observing at what point in the day they emerged from their pupal case. Most do this in the morning, but some come out later in the day. The fact that the researchers were then able to breed the late risers to produce more chronotypes like themselves indicated a genetic basis to the behavior.

From that, they then ran a DNA analysis on the flies during the 24 hours leading up to their emergence, and found that it wasn’t just the same genes being active at different times in both chronotypes, but that the genes themselves displayed differences.

As Tauber says, “looking at gene expression was only part of our research. An obvious question is what causes the different expression in the larks and owls. This difference is largely due to genetic variations in their DNA sequences - different gene versions that are present in larks and owls.”

This means that the molecular processes that contribute to the genetic clock in late risers is not merely delayed when compared to early birds, as was previously assumed, but entirely different. “Once a gene expression is delayed in Larks, a completely different cascade of molecular events is carried... The end point might be similar, but the different molecular routes result in a different journey time,” Tauber explains.

The research is of interest because, according to the authors, we are out of synch with our natural rhythms, and understanding how our genetic clock functions could help how we live and work. In the modern era, we have fallen into a system in which we work 9 to 5, and it’s becoming increasingly clear that this might not be the most productive or efficient structure for all workers.

#2

It does feel like I'm fighting against my body when it comes to my sleep schedule sometimes.

ScottyMcGee · #3

I remember reading something about how it depends how quickly your body temp rises in the morning or something like that. Maybe it's BS or something.

What would it mean though if you loved to sleep late and also wake up early? Are you just effing weird? (Because I do that)

Deepfake · #4

Yeah, I could tell, honestly. Then again, it wouldn't surprised me if this were impermanent.

#5

So where does that put me, the third -shift guy? Am I some kind of hideous tentacled abomination sharing only the remotest ancestry with modern humanity? Because that would be friggin rad.

I REALLY HATE POKEMON! · #6

They should be legally forced to let you work within your biological clock, then, or pay you extra or something otherwise.

#7

Interesting. I'm definitely a morning person... and so are the majority of our family.

smol Kat · #8

I've got one parent that's a morning person and one that's a night owl. I'm a night owl. My brother is one by necessity. Luckily, both of us (plus the morning-person parent) work jobs in which we must fill deadlines, and not report anywhere. Squeege's family is pretty much all night owls, and it's gotten to the point where I'm actually waking up first. I never thought this would happen and I'm so scared you guys!!

...ahem. But anyway. Is it known whether one chronotype is dominant?

Deepfake · #9

[QUOTE="nyankat, post: 1534963, member: 37303"]I never thought this would happen and I'm so scared you guys!![/QUOTE]
I actually have just about never really had that experience. I have stayed up well into the next day many times (or just skipped sleeping, because, whatever I'll do that some other time I guess) and people are always like 'oh hey you're up early' and I just give them the 'I haven't slept and the sounds you are making are irritating me' look in response. One does not simply speak with a day-walker.