Pears are one of the oldest fruit crops, with more than 3,000 years of cultivation history and are likely to have originated during the Tertiary period (65–55 million years ago) in southwestern China. In this study, researchers identified repetitive sequences of 271.9 Mb, accounting for 53.1% of the pear genome. By comparison with the apple genome, they found the size differences between pear and apple genome were mostly contributed by content diversity in transposable elements (TEs), while genic regions are similar in both species. Through comparative genomics and evolution analysis, researchers found pear, apple and strawberry shared an ancient whole-genome duplication (WGD) event that took place about 140 million years ago.

Jun WU et al., doi: 10.1101/gr.144311.112