The "Morning Person" Gene

German scientists have potentially discovered a genetic reason why some people are morning people whereas others are night-owls.

The gene called ABCC9 dubbed "morning person" gene was identified by analyzing 4251 individuals who reported their sleeping pattern.

The ABCC9 variant type and number of copies significantly affected the number of hours of sleep. To confirm this finding, scientists modified the ABCC9 gene in the fruit fly and obtained similar results.

The gene codes for a protein that senses the energy metabolism of a cell, but how this relates to sleep is unclear. The gene is also associated with other conditions including heart disease and diabetes which probably helps explain why quality of sleep seems to be associated with these disease processes.

In the past, it was thought that poor sleep "caused" cardiovascular problems, but just maybe, sleep problems and heart problems are caused by a common genetic trigger rather than one causing the other.

Reference:
A K(ATP) channel gene effect on sleep duration: from genome-wide association studies to function in Drosophila. Mol Psychiatry. 2011 Nov 22. doi: 10.1038/mp.2011.142. [Epub ahead of print]

Cold Sores Due to a Single Gene

Specifically, individuals who suffer from cold sores triggered by Herpes Virus Simplex - 1 (HSV-1) several times a year may have a single nucleotide polymorphism in their gene C21orf91 – dubbed rs1062202. Researchers have suggested it be called by the more "easy-to-remember" name Cold Sore Susceptibility Gene 1 (CSSG1).

Having this genetic change of swapping a thymine to a cytosine nucleotide was significantly associated (p=0.0047) with more frequent cold sores. Analysis has also found collections of 5 variants that are transmitted together with the C21orf91 gene of which two seemed to be neutral in terms of cold sore frequency, one was protective, and two were associated with increased susceptibility.

What does this all mean for an individual? It means if your parents get them a lot, than you may too.

Such individuals may benefit from regular use of anti-viral antibiotics to prevent such frequent recurrences.

Reference:
C21orf91 genotypes correlate with herpes simplex labialis (cold sore) frequency: Description of a cold sore susceptibility gene. J Inf Dis 2011; DOI: 10.1093/infdis/jir633.

Genetic Cause for Stuttering?

It appears that at least in some individuals, their stuttering may be caused by a genetic mutation, specifically a missense mutation in the N-acetylglucosamine-1-phosphate transferase gene (GNPTAB), which encodes the alpha and beta catalytic subunits of GlcNAc-phosphotransferase protein (part of the lysosomal enzyme–targeting pathway).

Other genetic mutations causing stuttering was found in the GNPTAB, GNPTG, and NAGPA genes. These genes encode enzymes that generate the mannose-6-phosphate signal, which directs a diverse group of hydrolases to the lysosome

This research was published in the February 2010 volume of New England Journal of Medicine.

Read the research here.