Open AccessThe behavior during pachynema of a normal and an inverted Y chromosome in Microtus agrestis
Author(s) -
ASHLEY TERRY,
JAAROLA MAARIT,
FREDGA KARL
Publication year - 1990
Publication title -
hereditas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.819
H-Index - 50
eISSN - 1601-5223
pISSN - 0018-0661
DOI - 10.1111/j.1601-5223.1990.tb00407.x
Subject(s) - synapsis , biology , chiasma , microtus , karyotype , chromosome , zoology , heterochromatin , genetics , gene
The pachytene behavior of the chromosomes of Microtus agrestis (L.) (Rodentia, Arvicolidae) males carrying either the standard, or the pericentrically inverted Lund Y chromosome have been examined by electron microscopy of microspread spermatocytes. There is no synapsis between the X and either the standard or the Lund Y chromosomes during any substage of pachynema. Since synapsis is generally considered a prerequisite for crossing over, there appears to be no opportunity for crossover or chiasma formation between the X and Y in this species. The G‐, C‐ and NOR‐banded mitotic karyotypes of animals carrying the standard and Lund Y are also presented.