Worm-like Marine Animal Providing Fresh Clues About Human Evolution
Although amphioxus split from vertebrates more than 520 million years ago, its genome holds tantalizing clues about evolution.
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The human genome has only about 25 percent more genes than the amphioxus genome, according to Holland. During evolution, humans have duplicated genes for different functions. Such duplication has given humans and other vertebrates a much larger “toolkit” for making various structures that are absent in amphioxus, including cells for pigment and collagen type II-based cartilage, for example.
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“The take-home message from this sequencing is that the human and amphioxus genomes are very much alike,” said Holland.