Homozygous viable, male sterile. Testes are much smaller than wild-type and are blocked before the first meiotic division. No evidence of any elongated or onion stage spermatids are observed. Instead testes are filled with cells that appear to remain at the primary spermatocyte stage. 16-cell cysts are still present, suggesting that the four mitotic division occur normally. however the cells are smaller and not as round as those seen in wild-type. Far from the apical tip of the testes cells appear to degenerate. In addition, some of the chromosomes fail to fully condense. Although meiosis is initiated in mutants, it is blocked after DNA synthesis but before the first meiotic division. In addition mutant testes show no sign of spermatid differentiation.