Seasonal observations on supernumerary chromososmes, mosaicism, and dynamics in two populations of the Eastern-Asian wood mouse (apodemus peninsulae, rodentia) from Primorskii Krai

摘要

Karyotypes of 47 individuals of the wood mice Apodemus peninsulae from two reserves in Primorskii krai were studied during spring, summer and autumn. In each population, variation in the number of B-chromosomes as well as the intratissue mosaicism determined by variation of the number, size and morphology of supemumerary chromosomes were described, Animals that have one dotlike B-chromosome were first described in both populations as rare variants. Individuals that have bone-marrow cell clones with two or three B-chromosomes were found to be predominant in the populations of Primorskii krai. The number of clones varied from one to three per animal. The frequency of mosaics showed seasonal variation. In the population of the Ussuriiskii reserve, a sharp increase in the frequency of anumals with a stable karyotype was detected in autumn, at the phase of increased numbers. The variation for mosaicism was suggested to correlate with the population numbers in mice and to indicate the genetic differences between generations of the population.