Generation Definitions
Mouse strain generation numbers provide additional information on the genetic background and breeding history of mouse strains that cannot be captured in the mouse strain names. The symbols and definitions for mouse generation numbers used by The Jackson Laboratory are listed below.
N |
Number of backcross generations. |
F |
Filial or inbreeding (sister X brother) generations. |
p |
Designates the generation when a strain was cryopreserved. |
+ |
Indicates the generation of a strain upon arrival at The Jackson Laboratory. Generation numbers before the "+" took place in the lab of the donating investigator; after the "+", at The Jackson Laboratory. |
? |
Used when the prior breeding history of a strain is not known. |
NE |
N-Equivalent is used when a mouse from a subsequent backcross generation is crossed back to a mouse from a prior backcross generation. |
G |
Generation is used primarily in mutagenesis schemes. |