Genetics & Molecular Biology

Can there be a genetic difference between progressives and conservatives?   Certainly we have had the discussion many times about studies, both sociological and biological, seeking to make the case that politics might be nature as well as nurture.
The jokes write themselves, really:

"Ozzy Osbourne's Genome Reveals Some Neandertal Lineage"

The idea itself is fascinating, though, and I am interested to see what more they can mine from the PoD (Prince of Darkness, to the uninitiated). I nominate the full contingent of Mötley Crüe as the next genetic guinea pigs, testing for why people who should by all accounts be dead are still alive and shouting at the devil.
Is alcoholism genetic as well as behavioral?  Studies have suggested it in the past and scientists at Brookhaven National Lab say they have the first experimental evidence of it.

Their study compared the brain's response to long-term alcohol drinking in two genetic variants of mice. One strain lacked the gene for a specific brain receptor dopamine D2, which responds to dopamine, the brain's "feel good" chemical, to produce feelings of pleasure and reward. The other strain was genetically normal.

In the dopamine-receptor-deficient mice (but not the genetically normal strain), long-term alcohol drinking resulted in significant biochemical changes in areas of the brain well know to be involved in alcoholism and addiction.

'Copy Number Variants' (CNVs) are hot. A CNV is a sizeable chunk of DNA that's either missing from your genome or present in extra copies. Chunks of DNA get copied or deleted on a surprisingly frequent basis. We've all got CNVs, most cases they are probably benign, but CNVs are becoming an increasingly appreciated as a significant source of medically important genetic variation. 'Recently appreciated' because we now have the technology to detect CVNVs reliably.
Two women who took part in the world's first controlled study of a genetic screening test before IVF have given birth to healthy babies.

The babies are the first deliveries in a pilot study of comparative genomic hybridization (CGH) by microarray, a new method of screening oocytes, female gametocytes involved in reproduction, before in vitro fertilization (IVF) for a full range of chromosomal disorders. 
The smallest entity of life is the single cell, which exists not only as single cell organisms, but as evolution proceeds, as members of a bigger and more complex living organism. During the progression of life, an organism encounters many experiences, and encodes these experiences as memories or knowledge.
Ever wonder what the smallest protein is? Apparently it's TRP-Cage, a protein with only 20 amino acids derived from the saliva of Gila monsters.

Trp-cage - smallest protein

You can find the structure file and images in the PDB database ( with PDB ID = 1L2Y. This highly stable mini-protein is important for studies of protein stability, protein folding, and 3D structure.

Even with this small size, it displays secondary structural elements, such as an alpha helix, found in many proteins. So far there are no known proteins with less than 20 residues, but we'll see what happens in the future.

The longest human protein is Titin with 34,350 amino acids. The smallest human protein is 44 amino acids but it could be an abortive translation from the 5' UTR of another mRNA. The smallest functional polypeptide is glutathione with only three amino acids.

BTW, proline is technically not even an amino acid much less a polypeptide. Chignolin is a man-made decapeptide so if you synthesize a GG dipeptide, it would be the smallest possible amino acid polymer.

Scientists have altered cardiac muscle cells to make them controllable with light and showed an ability to cause conditions such as arrhythmia in genetically modified mice, which opens up new possibilities for researching the development and therefore treatment of arrhythmias. 

Tobias Brügmann and his colleagues from the University of Bonn’s Institute of Physiology I used a “channelrhodopsin” for their experiments - a type of light sensor. At the same time, it can act as an ion channel in the cell membrane because when stimulated with blue light, this channel opens, and positive ions flow into the cell. This causes a change in the cell membrane’s pressure, which stimulates cardiac muscle cells to contract.
Stem cells help regenerate or repair damaged tissues, primarily by releasing growth factors that encourage existing cells in the human body to function and grow.

There has been an ongoing ethical controversy about human embryonic stem cell research but progress has been made nicely using adult stem cells, such as from marrow donors.