Cichlid Genome Resources
[ Genetic maps| BAC libraries| Physical maps| cDNA libraries ] The more than 25,000 species of bony fishes represent more than half of all living vertebrates.\n";echo "Among these, the perch-like fishes (Order Perciformes) includes more than 9,300 species (Nelson, 1994). \n";echo "We are working with laboratories around the world to develop genomic resources for one of the most \n"; echo "diverse groups of Perciformes, the family Cichlidae (>1500 species). Cichlids (pronounced 'siklids') \n"; echo " are found in tropical regions of the Americas, Africa, Madagascar and Sri Lanka, but achieve their \n";echo "greatest diversity in the Great Lakes of East Africa.\n";echo "The three major lakes in East Africa (Malawi, Tanganyika and Victoria) each harbor a separate radiation \n";echo "of several hundred species. The radiations in Lakes Malawi and Victoria have occurred in roughly the last \n";echo "million years, making this the most rapid rate of speciation known in vertebrates, and a fascinating system \n";echo "for studying the mechanisms of evolution and speciation. These fishes are also excellent model \n";echo "organisms for studying the genetic and developmental basis for differences in morphology and behavior.\n";echo "Tilapia (Oreochromis spp.) are cichlid fishes which shared a common ancestor with \n";echo "East African lake flocks about 10 million years ago. They are one of the most important \n";echo "species in aquaculture today, with world-wide production exceeding 1 billion \n";echo "pounds per year. Increasingly popular in western cuisine, tilapia are a particularly important \n";echo "source of protein in less developed countries.
\n";echo "The links and descriptions below will lead you to the genomic research tools we have developed so far.
\n";echo "- Genetic maps
\n";echo " - Our first linkage map was constructed from haploid embyros of O. niloticus (Kocher et al., 1998). This map can be viewed on the ArkDb viewer of the Roslin Institute.
\n";echo " - A second, more extensive map based on the F2 of an interspecific cross between O. niloticus and O. aureus is being prepared for publication (Lee et al. in prep), and is available on this www site.
\n";echo " - We recently published a third map based on the F2 of an intergeneric cross of two Lake Malawi cichlids (Metriaclima zebra and Labeotropheus fuelleborni (Albertson et al., 2003). This map is also available on this www site.
\n";echo " \n";echo " - BAC Libraries\n";echo "
Four tilapia BAC libraries have been produced at the Tokyo University of Fisheries\n";echo " (Katagiri et al. 2002). Plates and filters for portions of libraries 3 and 4 are available from the HCGS. Contact Federica DiPalma for more information.
\n";$table[] = array("Library","# primary clones","Average insert size","Estimated coverage","Picked");$table[] = array("1","120k","65k","6x","-");$table[] = array("2","800k","105k","65x","-");$table[] = array("3","100k","145k","11x","36k");$table[] = array("4","40k","194k","6x","33k");echo "\n";foreach($table as $row){ echo " \n"; foreach($row as $element) echo " | $element | \n"; echo "
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\n";echo "With funding from the NSF, we have produced a BAC library for the Lake Malawi cichlid Metriaclima zebra, which is described here. A library from the Lake Victoria cichlid Haplochromis chilotes (10x coverage, 128kb average insert size) has been constructed by (Watanabe et al., 2003) [PDF].\n";echo "
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\n";echo "- Physical maps\n";echo "
With support from the US Dept. of Agriculture, we have fingerprinted more than 35,000 clones from libraries 3 and 4\n";echo " (approximately 5x coverage of the genome). The assembled contigs can be viewed on our HCGS FPC viewer.
\n";echo "- cDNA resources (Coming soon!)
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