Monosomic lines are widely used to investigate in detail the genetic control of quantitative traits in wheat. In these experiments significant differences were found between monosomic lines and the euploid control in the expression of a large number of quantitative traits. In general, the absence of a critical chromosome accounts for these differences (Larson 1966; Maystrenko and Aliev 1986; Rigin and Barashkova, 1984). Near-isogenic lines are used for revealing the effect of conventional markers on other traits (Koval and Koval 1997) and the linkage to other markers including molecular markers (Muehlbauer et al. 1988). However, the incorporation of some genes into the genome or a longtime absence of any chromosome, may in a way lead to a decreased plant viability. In this case, the formation of the so- called compensatory complex of genes (CCG) can be expected in these lines after some generations of maintaining. The CCG was described in silkworm as a result of selection. for increased vitality in the inbred lines carrying semilethal genes (Strunnikov 1983). In these experiments, the individuals were selected with an increasing amount of minor alleles that compensated the harmful effect of the semilethal gene. These minor alleles acting additively form the CCG. In plants, the existence of CCG was shown in the experiments with diploid species Pisum sativum L., mutant chlorina. The CCG was transferred from the mutant line to the initial variety by several backcrosses. As a result, the line displaying the effect of stable heterosis was obtained (Sokolov 1990; Gostimsky et al. 1992). Thus, the CCG formation may bring about the variability in a number of traits including quantitative traits. This investigation reports the variability in genetic stocks of hexaploid wheat provoked by the aneuploid state of the genome. The results will be discussed in the light of possibility of CCG formation.