Recycling: Funds for Phones

Background: Channel catfish, Ictalurus punctatus, is the leading species in North American aquaculture. Genetic improvement of catfish is performed through selective breeding, and genomic tools will help improve selection efficiency. A physical map is needed to integrate the genetic map with the karyotype and to support fine mapping of phenotypic trait alleles such as Quantitative Trait Loci (QTL) and the effective positional cloning of genes. Results: A genome-wide physical map of the channel catfish was constructed by High-InformationContent Fingerprinting (HICF) of 46,548 Bacterial Artificial Chromosomes (BAC) clones using the SNaPshot technique. The clones were assembled into contigs with FPC software. The resulting assembly contained 1,782 contigs and covered an estimated physical length of 0.93 Gb. The validity of the assembly was demonstrated by 1) anchoring 19 of the largest contigs to the microsatellite linkage map 2) comparing the assembly of a multi-gene family to Restriction Fragment Length Polymorphism (RFLP) patterns seen in Southern blots, and 3) contig sequencing. Conclusion: This is the first physical map for channel catfish. The HICF technique allowed the project to be finished with a limited amount of human resource in a high throughput manner. This physical map will greatly facilitate the detailed study of many different genomic regions in channel catfish, and the positional cloning of genes controlling economically important production traits. Background Channel catfish production is now the leading aquaculture species in the U.S., with 600 millions pounds processed annually [1]. Consequently, selective breeding of catfish broodstock is ongoing in order to improve the genetic potential of the species for commercial production. To support selective breeding research, molecular tools are being developed to help researchers characterize the catfish genome, which consists of 28 pairs of autosomes and one pair of sex chromosomes, and identify genomic regions that control important production traits. However, a considerable amount of available data has not been organized within the structural framework of catfish chromosomes. Briefly, framework genetic linkage maps have been produced based on microsatellite loci [2] and Amplified Fragment Length Polymorphism (AFLP) loci [3]. Channel catfish Expressed Sequence Tags (EST) have been identified from several tissues [4,5] and clustered and annotated in the Gene Index Project [6]. A new EST project is underway through the Community Sequencing Program to sequence an additional 300,000 cDNA clones [7]. One cDNA microarray (L Hanson, personal communication) and one high density oligonucleotide array [8] have been developed for global gene expression studies. Published: 6 February 2007 BMC Genomics 2007, 8:40 doi:10.1186/1471-2164-8-40 Received: 27 October 2006 Accepted: 6 February 2007 This article is available from: http://www.biomedcentral.com/1471-2164/8/40 © 2007 Quiniou et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.