Complete loss of the dominant phenotype: less than 2% X chromosome non-disjunction. Homozygotes show the same meiotic phenotype as Axs^D/+, namely high levels of X and fourth chromosome non-disjunction, though the phenotype is less extreme than for Axs^r2 homozygotes. Effect is limited to homologous achiasmate segregations. Nondisjunction is not accompanied by a significant level of chromosome loss.