I've been laughing at this because they're calling it 'non-spotted', when really it looks more like they took the netting off a giraffe. It's spotted - it's just one full-body spot.
A lot of work on coat color genetics has been
done in domestic cats, not surprisingly (since they are deliberately bred for certain patterns and are accessible to study), but nothing similar to giraffe spotting exists in domestic cats, to my knowledge. Genetic controls of color patterns in animals in general is a fascinating topic. Hox genes (these are a type of
genetic toolkit that influence the pattern of head-to-tail differentiation of body parts across animal phyla) play an important role in color patterns in animals, though a lot of that work has been
done in insects. Oh, and they provide the explanation for
striping patterns in zebras.
I've heard that giraffes actually i
nherit important elements of their spotting pattern from their moms, and this mom is clearly spotted. As it turns out, the pattern and size of a baby giraffe's spots has a significant influence on its survival during its first few months of life (presumably when it is most vulnerable to predation), so yes to FoxyDee's question, this baby would likely be at a disadvantage in the wild.
The articles I've found about it aren't aimed at scientists, so there is no discussion of the possible genetics behind this very, very rare phenotype. There are a number of articles relating to the evidence that spotting patterns are inherited, but I'm not finding any that discuss the actual way the genes act to influence this pattern in giraffes.
So is there a spontaneous mutation that erased the baby's pattern? Possible, since it's incredibly rare to see this, even in captivity. Did it inherit two copies of a very rare recessive allele for spots? Possible, though it would have to be really rare, since we don't see this cropping up more than every several decades, even in the limited gene pools found in zoos. Does the baby still have the spotting genotype, but it was suppressed by a mutation in a genetic switch that prevented its ever turning on? Could something that happened in the womb have affected expression of the gene (seems unlikely, since this sort of thing is incredibly rare) at the epigenetic level?
