[Characteristics of the morphology and mitotic condensation of human Y chromosomes with structural rearrangements].

Parameters of the length and mitotic condensation were investigated in the following cases of Y-chromosome aberrations: isodicentric Y(q), Y-chromosome without heterochromatic block, and Y-chromosome with satellites. In the Ydic we revealed some differences between f-block, that is located near the inactive kinetochore, and the block near the active centromere. Satellites exert no influence on the mitotic function of Y chromosome, presumably owing to the presence of C-heterochromatic material. With the absence of heterochromatic region, a decline in condensation of the non-fluorescent segment was observed in addition to a simultaneous increase in its length. The mechanism of functioning of the structural heterochromatin is discussed.