It is nice to report on a well-known breed, albeit not that popular, which is considered to be inherently healthy by which I mean there are no genetically inherited health conditions. As you might be aware, very many cat breeds created out of a recessive genetic mutation have inherited health problems because these beads are inbred in order to make the recessive gene’s effects seen in the phenotype (appearance).
The gene that causes the ears of the American Curl to curl back is not the same one that causes the ears to fold flat in the Scottish Fold. It is a simple dominant gene which will give 50% curly-eared kittens in litters resulting from crosses between curled cats and plain ones.
“Breeding data indicate that the novel pinnate shape is inherited as a monogenic autosomal dominant trait. The mutant gene is designated as curl and symbolized by Cu.” – R. Robinson on the National Library of Medicine.
These kittens will be heterozygous for the gene that causes the ears to curl back which is symbolised by Cu. For heterozygous cats there are no inherited health problems but importantly, the same can be said for homozygous American Curl cats if Wikipedia is to be believed.
They asked the question whether homozygous American Curl cats (those with two copies of the Cu gene) will also be healthy, and they concluded that they will be. They say that observations of a CuCu cat over two years showed no sign of anomaly. But ‘anomaly’ they mean genetically inherited anatomical defects resulting in health issues.
This really does mean that the Cu gene does not import into the cat other changes to the cartilage in other parts of the body which are unwanted. The reason why the ears curl back is because the ear flaps are made of cartilage and this gene affects the growth of the cartilage.
The kittens are born with straight ears, which then curl up tightly within 24-72 hours. And over the next four months the tight curling starts to relax. Finally, the ears settle into their typical adult, semi-curled condition.
The health of this cat is also due to the fact that it has genetic diversity because the breeding includes mating with standard non-purebred cats as I understand it. This inherently imports into the breeding lines genetic diversity. And through that there is health. Conversely, inbreeding results in less genetic diversity which in turn results in health conditions developing.
However, the American Curl breeding results in a standard cat with curled ears. It is just the ears that distinguish this cat breed from all others.
So, health is a big positive for this cat breed. On the downside, you have to question why the breed was brought into existence. It started in 1981 in Lakewood, California. John and Grace Ruga found two stray kittens on their doorstep and one of them, a silky, longhaired black female stayed with them. They named her ‘Shulamith’. The name means “black but comely”.
They noticed her ears were strangely shaped and she gave birth to a litter of four kittens of which two had the same curled ears as their mother. They realised that they had the beginnings of a new breed.
Appearance – aesthetics
But the point is this: can we honestly say that ear flaps that curl back are attractive? The reason why the Scottish Fold is considered to be attractive is because their ears lie flat to the skull which gives them a baby-faced or an owl-like appearance. Both babies and owls are very popular because they have a rounded faces and big eyes.
RELATED: 23 facts about this breed.
This is where the popularity for the Scottish Fold comes from. But when the ear flaps curl back you do not create this attractive appearance. And therefore, the breed was started simply because it was different but that isn’t enough without more in my opinion.
And this is why, back in 1993, it was estimated that even after 12 years of breeding there were fewer than 1,000 American Curls in existence.
It is a breed that has certainly never featured in popularity listings. There are aficionados who like the breed but in general I think people would agree with what I have just stated. Spruce Pets say: “American Curls are ranked 27th among the United States’ most popular cat breeds.” The CFA recognise 45 breeds.
Below are some more pages on the American Curl.
Please search using the search box at the top of the site. You are bound to find what you are looking for.