Researchers decode rock pigeon genome

A team of international researchers has decoded the genome of the pigeon, 5,000 years after it was first domesticated, according to a study published Thursday. Known as Columba livia, the rock pigeon is considered among the most common and varied species on the planet, consisting of 350 breeds with a slew of different features, and is among just a few bird genomes sequenced so far. "Birds are a huge part of life on Earth, and we know surprisingly little about their genetics," said study co-author Michael Shapiro, an assistant professor of biology at the University of Utah. "This will give us new insights into bird evolution." Researchers found that a single mutation in the EphB2 gene, or Ephrin receptor B2, causes head and neck feathers to grow upward instead of downward, creating so-called head crests that help attract mates in many bird species. "This same gene in humans has been implicated as a contributor to Alzheimer's disease as well as prostate cancer and possibly other cancers," Shapiro said. The study, published on the website of the journal Science, also uncovered more conclusive proof that major groups of pigeon breeds originated in the Middle East. Shapiro said the study "found a lot of shared genetic heritage between breeds from Iran and breeds we suspect are from India, consistent with historical records of trade routes between those regions." The finding suggests "people were not only trading goods along those routes, but probably also interbreeding their pigeons," he added. According to the researchers, who used specially designed software, the rock pigeon's 17,300 genes compare to about 21,000 genes in humans. The study assembled 1.1 billion base pairs of DNA in the rock pigeon genome, compared to 3 billion base pairs in the human genome. Aside from the University of Utah, other institutions involved the study included China's BGI-Shenzhen, Denmark's University of Copenhagen and the University of Texas M.D. Anderson Cancer Center in Houston.