There have. The Japanese short tail gene is recessive. The Manx short tail gene is dominant. Both of these genes are common in their named areas of "origin" but have also been observed to occur spontaneously in other populations. Additionally, other novel mutations for short tails have occurred, but none that are currently known to be wide-spread enough to be studied.Toby is lovely. It sounds to me like the Japanese bob-tail mutation may be a recessive gene. The cat may have to get it from both parents, and since we all know that litters can have multiple fathers, well...
I wonder whether there have been any studies done on it.
Margret