Positional control of chiasma distribution in the house mouse. Chiasma distribution in mice homozygous and heterozygous for an inversion in chromosome 1.
An examination of the chiasma distribution in chromosome 1 of male mice homozygous and heterozygous for a distal inversion In(1) 12Rk and in normal males was carried out. No differences in chiasma distribution were found between homozygotes for the inversion and homozygotes for normal chromosome 1. A significant decrease in the frequency of bivalents bearing chiasmata in the pretelomeric region was found in heterozygotes. This, in its turn, produced a redistribution of chiasmata in the proximal non-inverted part of bivalent 1. These results could be interpreted as evidence for positional control of the chiasma distribution pattern: the distance of certain parts of the chromosome from the telomere and chiasmata interference are more important for determination of the chiasma frequency in a given region than its genetic content.
Gorlov
I P
IP
Institute of Cytology and Genetics, Academy of Sciences of the USSR, Novosibirsk.
Ladygina T
Y u
Yu
Serov
O L
OL
Borodin
P M
PM
D000818:Animals; D002871:Chromosome Banding; D007446:Chromosome Inversion; D002874:Chromosome Mapping; D003434:Crossing Over, Genetic; D005260:Female; D006579:Heterozygote; D006720:Homozygote; D007621:Karyotyping; D008297:Male; D051379:Mice / Q000235:genetics*