Cats
congenital defect. She was treated with hormones in January, 1961, and subsequently mated
to a chocolate point Siamese. This cross was made with the purpose of discovering if any
relationship existed between her phenotype and the albino series of alleles. A chocolate point
Siamese is homozygous recessive for a pigment-determining allele at the albino locus (cbcb),
for brown (bb) and for non-tabby (aa). [Note "+" meant "wild type" in the genetic nottion of
tht time.]
The cross produced a litter of three kittens, born 10 days prematurely with the result that
none survived. However, all were fully pigmented tabbies and therefore of the genotype
+acb+bb+aa. From the data it can be concluded that the phenotype of the mother was due (if
indeed genetically determined) to the homozygous recessive condition at some locus other
than that of the albino series of the black-brown alternatives.
annaabi.ee 
