Orientation of Implanted or Dissected Mouse Embryos for Histological Sectioning.

Histological analysis is an informative part of any mutational analysis. Interpretation of histological sections is much easier, and comparisons of mutant and wild-type embryos are more reliable if the plane of sectioning is precisely controlled. This protocol provides methods for obtaining sections with reproducible orientation for embryos between E4.5 and E9.5 still in the uterus and for dissected embryos E9.5 and older.