What is Polydactyl?

Polydctyly in felines refers to the congenital physical anomaly of having more than the usual number of toes. In cats, polydactyly is often benign and doesn't cause any harm to the animal. There are a number of genes that might cause this condition, but in felines specifically, the research is still somewhat limited. Here are some key points:

1. Maine Coon Polydactyl (MCPd):

   • The Maine Coon breed has a history of polydactyly, and specific genes responsible for this in Maine Coons have been identified.

   • This gene is considered autosomal dominant, which means that only one copy of the gene is needed for the trait to manifest. However, the expression can vary; some cats might have more toes than others even with the same genetic predisposition.

2. Pd gene:

   • The most commonly known gene responsible for polydactyly in cats is the Pd gene. When a cat has a dominant Pd allele, it usually shows polydactylism. If it has two recessive alleles (non-polydactyl), it doesn't display the trait.

   • Cats with a single copy of the Pd gene typically have extra toes. If a cat has two copies of this gene, it may show more pronounced effects, though this isn't always the case.

3. ZRS (Zone of Polarizing Activity Regulatory Sequence):

   • In many animals, including cats, a specific region in the genome called the ZRS plays a crucial role in limb development.

   • Mutations in this region have been linked to polydactyly in a number of species. In cats, specific variations in the ZRS are believed to contribute to the presence of extra toes.

There may be other genetic factors or pathways involved that are yet to be discovered or fully understood. Moreover, environmental factors during embryonic development can also play a role in the manifestation of physical traits, although there's little evidence of this in the context of feline polydactyly.

It's worth noting that while polydactyly is often harmless, there are instances where the extra toes or malformed digits can cause problems, such as nails growing into the paw pads or difficulty walking. In such cases, veterinary intervention might be needed.

When we discuss "good" and "bad" genes related to polydactyly in cats, we're generally referring to how these genes manifest and whether or not they result in medical issues for the feline. In some cases, polydactyl genes can lead to malformations that are more than just cosmetic and might require surgical intervention.

1. "Good" Polydactyl Genes:

   • These genes cause polydactyly that results in fully formed, functional extra toes. These additional toes often do not lead to any complications for the cat.

   • Such toes typically have a full set of bones and joints and are similar to the other toes in terms of functionality.

   • Cats with these kinds of polydactyl manifestations usually don't require any surgery or medical intervention related to their extra toes.

2. "Bad" Polydactyl Genes:

   • These genes cause polydactyly that results in poorly formed or dysfunctional toes.

   • Such toes might be "floppy", without full bone structures, or might not be fully separated from other toes. This can lead to complications like infections or injuries.

   • Nails on malformed toes can often become problematic. They might grow into the foot pad, leading to pain and infection. These nails often require regular trimming, and in some cases, if they consistently pose a problem, surgical removal of the toe might be considered.

   • In some cases, the extra toes or the structure of the foot might interfere with the cat's gait or cause discomfort. In these scenarios, a veterinarian might recommend surgical intervention.

If a cat has problematic manifestations of polydactyly, it's essential to get a veterinarian's advice on the best course of action. While many polydactyl cats never require surgery or any kind of medical intervention, those with more severe manifestations might benefit from surgical procedures to ensure their comfort and health.