Homozygotes produce 10-15% XO male self progeny; nondisjuction is correlated with an increased frequency of achiasmate X chromosomes in oocyte nuclei, and an unaltered distribution of X chromosome crossovers. Heterozygotes produce 1-2% male self-progeny. Homozygotes (and XO hemizygotes) are slower growing than WT; reduced male mating efficiency. me8 disrupts the function of the cis-acting X chromosome meiotic pairing center. Molecular studies show that the me8 chromosome carries a terminal deletion that removes >70 kb from the left end of the X chromosome, including the endogenous telomere; further, a segment of chromosome V has been translocated to the left end of X, and a new telomere has been added de novo to the end of the translocated segment.

Balanced heterozygotes are GFP+ Unc and segregate GFP+ Unc (heterozygotes), non-GFP non-Unc him-3(me80) homozygotes, and dead eggs (nT1 homozygotes). him-3(me80) homozygotes are viable and non-Unc. They produce more than 85% dead eggs and a large fraction (11%) of the survivors are males (Him phenotype). Cytologically they exhibit a reduced level of HIM-3 loading and fewer stretches of SYP-1 than WT. In diakinesis-stage oocytes, they contain a mixture of bivalents and univalents. Maintain by picking Unc.

Sperm activation in virgin males. Very poor sperm transfer.