Gene–Centromere Distances of Allozyme loci in Even- and Odd-year Pink Salmon, (Oncorhynchus gorbuscha)

We produced gynogenetic progeny families to estimate gene–centromere (G–C) distances of allozyme loci in even-year and odd-year pink salmon (Oncorhynchus gorbuscha). G–C distances of 37 loci distributed on a chromosome ranged from 1 cM at LDH-A1* to 49 cM at ADA-2*, DIA-2*, and sMDH-B1,2*. The distribution of the G–C distances along the chromosome arm was not even and appears telomeric. Eight loci in even-year and seven in odd-year showed high G–C distances (>45 cM), indicating that one crossover per chromosome arm is usual in pink salmon. Variation was observed in the results from different families; 14 loci out of 21 tested, showed heterogeneity. At mAH-3*, G–C distances from five odd-year families ranged from 6 to 37 cM; the widest range observed in this study. At isoloci such as sMDH-A1,2* and sMDH-B1,2* the distances from different families were grouped into statistically discrete distributions, suggesting that it may be a reflection polymorphism at both isoloci. It appears G–C distances in salmonid species are well conserved with some minor differences.