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Human

The first human genome was sequenced in 2001, and currently over 60 complete human genomes have been sequenced. These include the genome of researcher J Craig Venter, James Watson (who helped discover the double helix shape of DNA), a Han Chinese, a Yoruban Nigerian, a female leukemia patient and a Korean individual.

Comparison of these genomes to the genome of the chimpanzee and other organisms and looked at which seem to disappear in humans. These genes are likely to play an important role in what makes us humans, though only one held the code for an actual protein, the rest were involved in regulation or had other functions.

They found differences in the handling of several proteins, including ones in the brain, and ones that respond to male hormones. These changes resulted in bigger brains and changes in penis shape in response to a decrease in polyandry in humans. (Many other species have specially shaped penises, sometimes with spines, to compete with the sperm of other males.)