[Synapsis and recombination of chromosomes in the house mouse homozygous for the double inversion of the homogeneously stained regions in chromosome 1].
Examination of the meiotic pattern of chromosome 1 isolated from feral mouse population and containing a double insertion (Is) of homogeneously staining regions (HSRs) was carried out. In the previous study it has been shown that the region delineated by the proximal break point of Is(HSR; 1C5) 1Icg and the distal one of Is(HSR; 1E3) 2Icg is desynapsed during early pachytene and heterosynapsed at midpachytene. No synaptic disturbances were revealed in homozygotes in this study. Chiasma frequency in hetero- (1.87) and in homozygous (1.88) males was shown to be higher than in normal ones (1.61). Thus, insertion of recombinationally inert heterochromatic regions leads to increase in the length of genetic map of the chromosome via physical elongation and relaxation of interferential restrictions.
I P
IP
Gorlov
T Iu
TIu
Ladygina
P M
PM
Borodin
D000818:Animals; D007446:Chromosome Inversion; D005819:Genetic Markers; D006720:Homozygote; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D051379:Mice / Q000235:genetics*; D011995:Recombination, Genetic; D013194:Staining and Labeling
D005819:Genetic Markers
Sinapsis i rekombinatsiia khromosom u gomozigot po dvoĭnoĭ inversii gomogenno okrashivaemykh raĭonov v 1-ĭ khromosome domovoĭ myshi.