Double helix

It's good to be reminded every now and then of the depth and beauty of the revolution in understanding that Watson and Crick facilitated in 1953:

A vital gene that defends us against cancer has been found in one of the simplest of [multicellular] animals – a...placozoan. The discovery shows that p53, sometimes described as the "guardian of the genome", has been around for over 1 billion years...Human p53 is a closer match to the placozoan version than it is to counterparts in more closely related animals such as flies and worms.

-- from DNA's guardian gene found in placazoans

Pleiotropy makes a dragon

Pharyngula explains.

Snakes evolved limblessness about 150 [?] million years ago, so if this for real then it is quite a throwback.

A more common mutation, it's reported, is a snake with two heads.

Cheerful asymmetry

Look at yourself in the mirror. You're probably mostly symmetrical: one eye and one ear on each side of your head, features that are at least roughly even, and any lopsidedness is most likely due to postnatal wear and tear.

Deep inside you, though, you are profoundly asymmetrical, and that asymmetry is essential for your well-being.

And you share this with snails! P Z Myers explains.

RNA 'bestiary'

...in this graphic, which is part of an NYT package that includes articles on an 'identity crisis' for the gene, the promise and power of RNA and looking beyond 'gene'.


The third article quotes Evelyn Fox Keller:

the notion of the gene as the atom of biology is very mistaken...DNA is a far richer and more interesting molecule than we could have imagined when we first started studying it.

A life's bugs

Bacteria in the human microbiome collectively possess at least 100 times as many genes as the mere 20,000 or so in the human genome.

-- Science, NYT.