Cynoglossus semilaevis: Whole Genome Sequence

On July 31 2010, Yellow Sea Fisheries Research Institute (YSFRI) Chinese Academy of Fishery Sciences and BGI (Formerly known as Beijing Genomics Institute, headquarter at Shenzhen), jointly announced the complete sequencing and assembly of Cynoglossus semilaevis genome. It is the first Pleuronectiformes that have been fully sequenced and also the first fish genome to be sequenced in China.

C. semilaevis (Half-smooth tongue sole) is a marine fish. It has a ZW sex determination type in which females has heteromorphic chromosome and grows 2-4 times faster than males. The genome project of C. semilaevis was jointly launched by YSFRI and BGI in December 2009, with the aim to sequence the whole genome of C. semilaevis using next-generation sequencing technology. The genome is successfully assembled by BGI using its self-developed assemble and analysis tools. The research revealed that the C. semilaevis genome size is 520Mb (5.2 million nucleotides), containing 9.5% repeat sequences. More than 20,000 genes were found, of which more than 18,000 can be identified with homologous genes in other species. The other 2000 genes have no homologous gene identified.

The C. semilaevis genome sequencing has generated an enormous database of genetic information that can be used to understand the genetic basis of important traits such as sex determination. The joint research is part of BGI’s "1000 Plant and Animal Reference Genomes Project" which plans to decode 1000 genomes of plants and animals of great economic and scientific value.

Takifugu rubripes: Whole Genome Sequence

Fifth Fugu Genome assembly v5 made available by the Institute of Molecular and Cell Biology (IMCB) in July 2010. The fugu (Takifugu rubripes or Fugu rubripes) genome project was initiated in 1989. In 1993, researchers showed that the fugu genome is only 390 Mb, yet it contains a similar repertoire of genes to humans, which is useful for discovering genes and gene regulatory elements in the human genome. Fugu is the second vertebrate genome to be sequenced, the first being the human genome. A ‘draft’ sequence of the fugu genome was determined by the International Fugu Genome Consortium in 2002 using the 'whole-genome shotgun' sequencing strategy. In the latest version, some gaps in the fugu assembly v4 have been filled and the scaffolds have been organized into chromosomes based on a genetic map of the fugu (a collaborative project between IMCB and University of Tokyo). The v5 assembly comprises 7,118 scaffolds covering 392 Mb. About 72% of the assembly (281,557,002 bp) is organized into 22 chromosomes. Another 14% of the assembly (55,560,038 bp) is assigned to chromosomes but the orientation and order of the scaffolds are not known (Chr_n_un). The remaining 14% of the assembly (54,753,918 bp) is concatenated into a single sequence (Chr_un).