More than 500 million years ago, the DNA of a primitive chordate sea creature underwent two successive doublings, allowing for the evolution of the complex internal communication between cells that led to the evolution of vertebrates.
Now, researchers have sequenced the genome of the amphioxus, a modern marine invertebrate that did not undergo the genome duplications and is believed to be similar to the original vertebrate ancestor. By comparing the amphioxus genome to the human genome, the study, published today (July 24) in Open Biology, provides insights into how the duplications boosted cells' ability to integrate information, but also reveals how breakdowns in cellular communication cause diseases like cancer, diabetes, and neurological disorders.
“Amazingly, what happened so long ago still affects the life and diseases of modern humans,” said co-author Carol MacKintosh, of the University of Dundee, in a press release. MacKintosh and colleagues are investigating the protein-coding gene duplicates that stem from the two genome doublings to understand their influence on modern humans. "We already have clues about important questions, such as why did only certain genes survive the DNA doublings, how did they shape vertebrate evolution, and what is their impact on human health and diseases?”