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Ever wonder why some people are always so agressive and so hard to get along? well… researchers have recently identified an agression gene in Fruit Flys Drosophila melanogastar (not so fruity after all huh?). See below:

Researchers Herman Dierick and Ralph
Greenspan of The Neurosciences Institute in San Diego, California, set
out to see if they could breed high levels of belligerence back into
lab strains and to learn what genes might be implicated. They designed
a cage in which 11 small containers of fly food were evenly spaced to
serve as distinct "territories" for the insects.  120 Males+ 60 females were introduced to this environment.  Only the
males deemed most aggressive–as judged by behaviors such as charging,
lunging, holding, and tussling–were removed and mated (score!).

After 20
generations, the aggressive insects scored more than 30(!) times higher
than the controls did on a "fighting index" that measured how
ferociously they fought, Dierick and Greenspan report. To see what genes might be involved in
this increased aggression, the team used microarrays to look for
differences in gene expression in fly brains. Several dozen genes were
expressed differently in the superaggressive flies, compared to
controls, but flies with mutations in one gene called Cyp6a20
were especially combative. This gene encodes one of a group of enzymes,
called cytochrome P450s, which are involved in a number of biological
processes including development, reproduction, and detection of
pheromones.

Source: Dierick and Greenspan Nature Genetics, August 13, 2006.  Also see Trudy MacKay in a similar study from PLOS Genetics on August 2nd, 2006

To what extend are we different from primates? what makes us human and others just animals, albeit sharing 96% of our genome?  Prof. David Haussler, a revolutionary thinker, a computer scientist, and now a self-taught geneticist used aligned sequences from many animals and compared with human sequences.  He was able to identify regions with large number of changes within humans but virtually none in all other species, which are closedly related with humans, and he indicated these human lineage-specific changes. 

In particular, he discovered an RNA-gene that is highly expressed with reelin, a regulator of brain (cortical) development.  This gene is expressed in a type of cells called Cajal-Retzius cells of the subpial granular layer, a layer thought to contain the Cajal-Retzius neurons and their precursors migrating tangentially from the outside the neocortex (unique in human).  It is also present in the upper cortical plate, presumably representing the cells that are finishing up their radial migration.

source: Pollard et al, Nature 2006 (august 16th) doi:10.1038/nature05113, advanced publication online.