Are you NOT a morning person? Do you have tendencies to feel like punching the person that just woke you up? Do you run out of money because you constantly destroy alarm clocks? Rejoice because now you have a genetic excuse for your irrational crankiness.

A team of German scientists will be presenting a genetic basis for human morning lark behavior in an upcoming G&D paper. The team has apparently uncovered a genetic cause for human Familial Advanced Sleep Phase Syndrome (FASPS), which causes people to both go to sleep and wake up very early.

If you're not a morning person you probably don't have that gene.

"Being a morning lark or a night owl is something encoded in people's genes and we here made substantial progress to uncover the molecular basis for that," explains Dr. Achim Kramer of Charite Universitaetsmedizin Berlin.

FASPS is a dominantly inherited circadian rhythm disorder, basically both parents' inborn biological clocks (or scientifically known as the circadian clock) run in advance. If both parents have it, likelyhood is that the kid will too. FASPS patients' periods are about 4 hours advanced, causing the patients to retire at 6 or 7pm and rise by 4am.

This bit gets a little technical so bear with me.

In 1999, it was discovered that a mutated gene, called PERIOD2 (PER2) is mutated in many cases of FASPS. Dr. Kramer and colleagues mapped phosphorylation sites on the PER2 protein. They identified 21 sites, one of which (Serine 659), was implicated in FASPS. By monitoring the bio-luminescence cycles of cell lines, the researchers demonstrated that mutation of Serine 659 causes a shortening of the luminescence period and recapitulates the FASPS phenotype. The researchers determined that the mutated form of Serine 659, which does not get phosphorylated, leads to PER2's destabilization and earlier clearance from the cell nucleus.

They then went on to show that mutations of other PER2 phosphorylation sites have differential effects on PER2 protein stability, circadian period length, and organismal behavior.

Basically, mutation in that particular protein directly affects circadian period length. Dr. Kramer adds that "This is the first example where the regulation of a complex human behaviour could be really nailed down to its genetic basis and molecular mechanism."

I wonder if in the future they could program my genes so that I'll always be able to wake up in time for work?