Strains used

  • The C57BL/6 strain was used for generating mutant lines.
  • NIMR:Parkes was an outbred (random-bred) strain available at the Francis Crick Institute, Mill Hill Laboratory, and was used to generate reference image data of wild-type mice.

Somites and crown-rump length

The number of somites and the crown-rump length of embryos were determined from a 3D model created using Osirix software. The crown-rump values given are only approximate because the embryos shrink to some degree during fixation. All somites were counted until stage E12.5, however beyond this stage it is difficult to determine somite number accurately so we have adopted the convention used in "The Atlas of Mouse Development" by M.H. Kaufmann 1992 (ISBN 0-12-402035-6).