Table 4. Variability in mutant phenotype penetrance.

Every distinct phenotype scored in each line was listed along with its penetrance (i.e. the number of embryos showing the phenotype divided by the total number of embryos analysed for that line). Scored phenotypes were then ranked by penetrance value to obtain the proportions falling within the four ranges shown. (Note that all data from the lines Otud7b, Npat and Dhx35 were removed from the analysis, since in each case, these were obtained from examination of a single embryo).

Penetrance range	Phenotypes scored (homozygous mutants)	%
<25%	673	55.21%
26–50%	343	28.14%
51–75%	118	9.68%
>75%	85	6.97%