Surprise of the Day - Zebrafish Genome 'Published'

Zebrafish is an important model organism to study vertebrate development. Ask a geneticist whether zebrafish genome was published before or after human genome and most will hesitantly say ‘after’. If you ask how many years after, we doubt anyone will give a number greater than 4. The genome had been publicly available for so long that most researchers do not know that it was not backed by an ‘official genome paper’.

That status finally changes today, not sure whether due to BGI competition.

The Zebrafish Reference Genome Sequence and its Relationship to the Human Gen ome

Zebrafish have become a popular organism for the study of vertebrate gene function1, 2. The virtually transparent embryos of this species, and the ability to accelerate genetic studies by gene knockdown or overexpression, have led to the widespread use of zebrafish in the detailed investigation of vertebrate gene function and increasingly, the study of human genetic disease3, 4, 5. However, for effective modelling of human genetic disease it is important to understand the extent to which zebrafish genes and gene structures are related to orthologous human genes. To examine this, we generated a high-quality sequence assembly of the zebrafish genome, made up of an overlapping set of completely sequenced large-insert clones that were ordered and oriented using a high-resolution high-density meiotic map. Detailed automatic and manual annotation provides evidence of more than 26,000 protein-coding genes6, the largest gene set of any vertebrate so far sequenced. Comparison to the human reference genome shows that approximately 70% of human genes have at least one obvious zebrafish orthologue. In addition, the high quality of this genome assembly provides a clearer understanding of key genomic features such as a unique repeat content, a scarcity of pseudogenes, an enrichment of zebrafish-specific genes on chromosome 4 and chromosomal regions that influence sex determination.