W11,P341
We have constructed a genetic map for a tilapia (Oreochromis niloticus) using DNA markers. The segregation of 62 microsatellite and 112 anonymous fragment length polymorphisms (AFLPs) was studied in 41 haploid embryos derived from a single female. We have identified linkages among 162 (93.1%) of these markers. The map spans 704 Kosambi centimorgans in 30 linkage groups covering the 22 chromosomes of this species. Twenty-four of these linkage groups contain at least one microsatellite polymorphism. From the number of markers linked 15 or fewer cM apart we estimate a total map length of approximately 1,100 cM. High levels of interference were observed. A microsatellite polymorphism in the prolactin locus has been added to this map, and a highly suggestive linkage of the blonde color locus also has been identified. Details on the map can be accessed on the WWW at http://tilapia.unh.edu.