An. Milishnikov et al., GENOTYPIC VARIABILITY IN POPULATIONS OF MOUNDBUILDER MICE MUS-SPICILEGUS PET., 1882, AT DIFFERENT LIFE-CYCLE STAGES, Genetika, 34(7), 1998, pp. 947-952
Genotypic variability in two Moldovian populations of moundbuilder mic
e Mus spicilegus Pet. was examined at different stages of their life c
ycle - at the beginning of overwintering in mounds and in the middle o
f summer in agrocenoses. Thirty allozymes were assayed. Significant di
fferences in allele frequencies and heterozygosity between overwintere
d and mice born in the year of the experiment were recorded only for I
dh-1. This fact was related to the presence of differential mortality
among overwintered mice in the populations by the middle of summer. Th
e increase in heterozygosity for Idh-1 in the populations occurred bec
ause of ''old'' mice that lived until the middle of summer, at which p
oint they still have not contributed to the gene pool of the populatio
n. The generic effect of the annual separation of generations of mound
builder mice due to their overwintering in mounds is analyzed. Overwin
tering has a bottleneck effect on the population The relatively low ge
netic variability in moundbuilder-mice populations is considered with
regard to their biological and ecological features. Based on obtained
data, a conclusion on the high genetic stability of moundbuilder-mice
populations during their entire life cycle is made.