Genetic Pleiotropy and the Risks in Breeding Recessive Mutations

Nearly everyone loves what’s rare and unique. A slight defect in the minting process of a coin can create a demand and a value well beyond the face value of the coin. The coin is functionally no different than its perfectly minted counterpart, but its scarcity and uniqueness alone make it more desirable than the rest.

- Lucy Drury

A Rare … Cat?

The cat fancy is no different. Many of our breeds are preserved or created based on a defect – the tailless Manx, the curly coated Rexes, the sparsely coated Lykoi, the naked Sphynx. People love Scottish Folds and American Curls for their uniquely folding ears, and American or Japanese Bobtails for their cute, poofy tails. Rare and flashy colors are popular, too. Lilacs, chocolates, cinnamon, goldens, bi-colors, and patched or calico males are very popular. Though we don’t like to think of these charming variants as defects, that’s what they are. Whether we call them variants, mutations, or defects, from a genetic point of view they are the same thing. Just like the rare coin created from a flaw in its minting process, genetic variants are created in much the same way – something goes awry in a cell’s duplication process, causing an error in the sequence of the nucleic acids that make up an organism’s DNA. Since genes come in pairs, nature has a backup system, and if one copy of an allele (one of two or more versions of a genetic sequence at a particular location on a chromosome) is defective, the other likely is not.

Time Will Tell …