Penetrance of selected phenotypes in the <i>Sulf1</i>^−/−<i>Sulf2</i>^−/− animals.

Refer to text for complete description of phenotypes observed. Abbreviations used: BO, basioccipital; BS, basisphenoid; w, weeks. 1Frequency defined as the number expected (by standard Mendelian segregation, see Table 2) divided by the number observed; n defined as total number of animals analyzed in a given age range 2Frequency defined as the percentage of Sulf1−/−Sulf2−/− embryos that showed the described phenotype; n was the number of Sulf1−/−Sulf2−/− embryos analyzed 3Frequency defined as the percentage of Sulf1−/−Sulf2−/− animals whose mean volume for the kidney or indicated bone was less than the smallest of the control animals' kidney or bone volumes; n as the number of Sulf1−/−Sulf2−/− animals analyzed