© 2004 The American Genetic Association
Genetic Linkage Mapping of Allozyme Loci in Even- and Odd-year Pink Salmon (Oncorhynchus gorbuscha)
From the Juneau Center, School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, 11120 Glacier Highway, Juneau, AK 99801 (Matsuoka, Gharrett, and Smoker), and the Auke Bay Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanographic and Atmospheric Administration, 11305 Glacier Highway, Juneau, AK 99801–8628 (Wilmot). M. P. Matsuoka is currently at the National Research Council, Institute for Marine Biosciences, 1411 Oxford St., Halifax, NS, B3H 3Z1, Canada.
Address correspondence to Makoto P. Matsuoka at the address above, or e-mail: makoto.matsuoka{at}nrc-cnrc.gc.ca.
We constructed genetic linkage maps of allozyme loci in even- and odd-year pink salmon (Oncorhynchus gorbuscha), using the total of 320 families (each female was crossed with two different males, and 80 females and 160 males were used for each of even year and odd year). The maps include eight linkage groups involving 22 loci. We observed substantial variation in recombination frequencies among different families within broodline and between sexes within broodlines. In the linkage analysis between sAAT-3* and sMDH-B1,2*, two even-year families and one odd-year family exhibited evidence of association, but two even-year and one odd-year families did not. Recombination rate tends to be reduced in males in pink salmon. The ratio of recombination rate (female/male), which ranged from 1.7 to infinity, averaged 2.8 in the even-year crosses and 3.2 in the odd-year crosses. The linkage groups (LG) I and II involving sAAT and mAH loci, which probably duplicated in the recent tetraploidization event, and the orders of loci in the LGs I (sAAT-3* 
mAH-4*) and II (mAH-3* sAAT-4*) were reversed, suggesting the possible paracentric inversion during salmonid evolution after the duplication.