Animals die during embryonic development. In C. elegans, often assayed as refractile eggs that fail to hatch; when applied to large-scale RNAi screens in C. elegans, more than 10% of embryos die.
Higher numbers of male progeny occur in the population compared to control populations. In C. elegans, the high incidence of males phenotype in a self-fertilizing hermaphrodite population is a result of an increase in X chromosome nondisjunction.
Variations in the specialized nuclear and cytoplasmic divisions of a single diploid cell, whose specific outcome is the formation of four haploid daughter cells compared to control. Meiosis occurs during the formation of gametes.