tailieunhanh - Báo cáo y học: "Insights into vertebrate evolution from the chicken genome sequence"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học quốc tế cung cấp cho các bạn kiến thức về ngành y đề tài: Insights into vertebrate evolution from the chicken genome sequence. | Minireview Insights into vertebrate evolution from the chicken genome sequence Rebecca F Furlong Address Department of Zoology University of Oxford South Parks Road Oxford OX1 3PS UK. E-mail Published 31 January 2005 Genome Biology 2005 6 207 The electronic version of this article is the complete one and can be found online at http 2005 6 2 207 2005 BioMed Central Ltd Abstract The chicken has recently joined the ever-growing list of fully sequenced animal genomes. Its unique features include expanded gene families involved in egg and feather production as well as more surprising large families such as those for olfactory receptors. Comparisons with other vertebrate genomes move us closer to defining a set of essential vertebrate genes. The earliest bird fossils from the genus Archaeopteryx date back to the upper Jurassic period 1 around 150 million years ago. They show a mixture of dinosaur-like and birdlike features and lend support to the now widely accepted theory that birds evolved from dinosaurs. Birds are thus along with most extant reptiles members of the diapsid lineage which split from the mammalian synapsid lineage around 310 million years ago. Chickens were domesticated over 7 000 years ago reviewed in 2 and are still of tremendous agricultural importance and they have long been a model for biological research in fields ranging from embryology and development to virology and cancer. In addition the phylogenetic position of the chicken between fish and mammals makes it ideal for comparative genomic analyses. It therefore came as no surprise when in March 2003 the first complete avian genome sequence was initiated using the model for the undomesticated chicken the red jungle fowl Gallus gallus . Remarkably barely one year later an initial draft assembly based on a coverage of the genome was released into the public databases. The International Chicken Genome Sequencing Consortium 3 now reports an .