Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Identify Cause of "Early Bird" Sleep Disorder

31.03.2005


A few rare people who consistently nod off early, then wake up wide-eyed much before dawn, can blame a newly-found mutant gene for their sleep troubles, Howard Hughes Medical Institute researchers announced today.



This odd “time-shift” trait — called familial advanced sleep phase syndrome (FASPS) — was studied in one affected family by neurologist Louis J. Ptacek, a Howard Hughes Medical Institute researcher, and Ying-Hui Fu, at the University of California, San Francisco. Their report appears in the March 31, 2005, issue of the journal Nature.

The sleep-shifting mutation they found is in “a gene that was not previously shown in mammals to be a circadian rhythm gene,” Ptacek explained. It’s not yet clear how the mutant gene works to shift people’s sleep time, their circadian rhythm, he added. But follow-on experiments in fruit flies and mice yielded results that are intriguing.


When the mutant gene was inserted into the flies, for example, it did the opposite of what was seen in the human family: it lengthened circadian rhythm. Yet in genetically engineered mice, the same gene change made the mice early risers — mimicking what was seen in humans with FASPS.

So, studies of all three organisms — flies, mice and humans — “will help us understand the similarities and differences” in how the gene works in different settings, in different genetic backgrounds, he said. Experiments can be done in mice and flies, with results applying to humans, while the studies of humans can inform what’s being seen in the flies and mice.

In addition, “these results show that the gene is a central component of the mammalian circadian clock, and suggest that mammalian and fly clocks may have different regulatory mechanisms, despite the highly conserved nature of their individual components," the research team wrote in Nature. Such studies may help unravel some of the fundamental mysteries of how circadian rhythms are established and maintained in creatures that have evolved along very different paths.

As for the affected individuals, Ptacek said most are able to live normal lives, and some are proud of being able to arise before dawn and get a lot done while everything is quiet. A few, however, are constantly bothered by living out of sync with everyone else’s daily schedule.

“Some of them would never come to a doctor” to find out what’s going on with their sleep pattern, Ptacek said, “because they aren’t troubled by it. Often, they have adjusted and accommodated their jobs to match their ability. But others are bothered by being out of phase with the rest of the world.”

He said the FASPS subjects don’t seem to sleep any more or less than other people; they just sleep at different times. And there is apparently no connection to the better-known problem called narcolepsy.

Ptacek said it was also found — in the family’s six affected individuals — that “they all have asthma, and they all have migraine headaches, with aura. Now, that could be purely coincidental, but a more important possibility is that these are part of the same syndrome.” So far, however, “we haven’t even looked at that yet.”

He estimated that a very small number (about .3 percent) of the human population seems to have this “circadian clock” shift. And in earlier research, Ptacek and his colleagues had discovered an entirely different gene that causes a similar clock-shift. Both arise because of so-called point mutations in the genes. This means that altering a single base-pair in the gene’s long DNA chain is enough to change a person’s sleep behavior. Evidence from tissue culture experiments with the second gene suggests the change causes a protein — an enzyme called a kinase that is made by the gene - to be less active than normal.

The lead author of the paper in Nature is Ying Xu, a member of the team in San Francisco. Other team members are at the University of Vermont and the University of Utah.

Jim Keeley | EurekAlert!
Further information:
http://www.hhmi.org

More articles from Life Sciences:

nachricht Toward a 'smart' patch that automatically delivers insulin when needed
18.01.2017 | American Chemical Society

nachricht 127 at one blow...
18.01.2017 | Stiftung Zoologisches Forschungsmuseum Alexander Koenig, Leibniz-Institut für Biodiversität der Tiere

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>