The cocoa mutation arose spontaneously on the C57BL/10J background at The Jackson Laboratory in 1978 when that inbred was at generation F136. This mutation was maintained through sibling inbreeding and in 1985 homozygous males at generation F136+6 were bred to C57BL/6J females to generate embryos for cryopreservation. In 2000 embryos were thawed and the line was subsequently maintained by intercrossing.
|Allele Synonym(s)||co; coa|
|Gene Symbol and Name||Hps3, Hermansky-Pudlak syndrome 3|
|Gene Synonym(s)||SUTAL; coa; cocoa|
|Strain of Origin||C57BL/10J|
|Molecular Note||The underlying mutation responsible for the phenotype in the cocoa mouse was identified as an A to T substitution in the 3' splice site of the gene. A cryptic splice site is utilized within exon 15, which results in a frameshift. Northern analysis demonstrated qualitative and quantitative differences in mRNA between wild-type and homozygous mutant animals.|