The research team unraveled the specific regions of the parrots' genome using a new technology, single molecule sequencing, and fixing its flaws with data from older DNA-decoding devices. The team also decoded hard-to-sequence genetic material from corn and bacteria as proof of their new sequencing approach.
The results of the study appeared online July 1 in the journal Nature Biotechnology.
Single molecule sequencing "got a lot of hype last year" because it generates long sequencing reads, "supposedly making it easier to assemble complex parts of the genome," said Duke University neurobiologist Erich Jarvis, a co-author of the study. He is interested in the sequences that regulate parrots' imitation abilities because they could give neuroscientists information about the gene regions that control speech development in humans.
Jarvis began his project with collaborators by trying to piece together the genome regions with what are known as next-generation sequencers, which read chunks of 100 to 400 DNA base pairs at a time and then take a few days to assemble them into a draft genome. After doing the sequencing, the scientists discovered that the read lengths were not long enough to assemble the regulatory regions of some of the genes that control brain circuits for vocal learning.