{"Procedure":"
    \t
  1. \t\tSet up timed mating with heterozygous animals. Aim to dissect and collect >=28 alive embryos, otherwise lethal and subviable calls cannot be made. If more than three homozygous pups are produced before 28 pups are genotyped, a viable call can be made.
    2. \t
  2. \t\tCollect tissue for genotyping and (OPTIONAL) score Gross Morphology and/or process for Histopathology and or Imaging.
    3. \t
  3. \t\tGenotype all embryos and \t\t
      \t\t\t
    1. \t\t\t\tStrains that produce NO existing homozygous embryos will be considered LETHAL (complete embryonic lethality [MP:TBC]).
      2. \t\t\t
    2. \t\t\t\tStrains that produce NO live (absence of heartbeat) homozygous embryos will be considered LETHAL (complete embryonic lethality [MP:TBC]).
      3. \t\t\t
    3. \t\t\t\tStrains that produce live homozygous embryos but with an obvious defect will be left to the discretion of the center with the decision and reason recorded in the parameters.
      4. \t\t\t
    4. \t\t\t\tX-linked strains that produce NO live hemizygous male embryos from female carriers will be considered LETHAL (complete embryonic lethality [MP:TBC]).
      5. \t\t
    \t
    4. \t
  4. \t\tFlag strains that produce less than normal numbers of homozygous/hemizygous male progeny\t\t
      \t\t\t
    1. \t\t\t\tStrains that produce <50% expected homozygous progeny will be annotated as partial embryonic lethality [MP:TBC].
      2. \t\t\t
    2. \t\t\t\tX-linked strains that produce <50% expected male hemizygous progeny from female carriers will be considered partial embryonic lethality [MP:TBC].
      3. \t\t
    \t
","Purpose":"

\n\tTo assess the viability, sub-viability, and lethality of homozygous embryos at E9.5

\n","Experimental Design":"","Notes":"

Recording data for X-linked lines

As the procedure does not allow recording of hemizygous males specifically, hemizygous males should be recorded as homozygotes in this procedure.

 

\tData QC

\tAll genotypes should be collected using validated assays.

\tY chromosome assay required for X-linked lethal strains.

\tData Analysis, annotation and display (+statistics)

\tPreliminary: No analysis required as it is a line level procedure. This could change with additional data about the procedure.

\tSee E9.5 Gross Morphology protocol for MP calls of specific phenotypes at this time point.

\tYolk sacs that have no visible embryos are counted as dead embryos.

\tTotal Embryos: All, WT, Het, Hom
\t    •Alive, dead, and defect (all genotyped)
\tTotal Dead: All, WT, Het, Hom
\t
\tTotal Defect (Alive or Dead):  All, WT, Het, Hom
\t    •Abnormal and dead embryos
\tLitter size: all genotyped embryos
\t    •ignore partials and reabsorptions.

"}