i have a manx/polydactyl/bengal cat it was born with a tail but all its

sisters&bros were born with no tail... and its mom has no tail.if my cat breeds with a cat that also has a tail its will its kittens be born with tails or without tails?

The reason a manx has no tail is actually a physical defect. Their spine is curved wrong which prevents the tail from growing. Just like human disablities, the manx defect is in their genes. So yes, there is a possible that the kittens may have no tail. Because of the defect there is no way that two manx are able to mate, so there is no for sure way to have a full litter of manx. When breeding manx it will always be a toss up as to how meny of what you get per litter. (Sorry for using the word "defect". I was unable to come up with a better word).
PS Yes you can have a cat like you have decribed above. Please disregard answer one.

A what?

I have had manx for years and not even pure bred Manx always have tail-less kittens.

Nice try, no such thing as a manx bengal, and polydactyl isn't a breed.

If it is a triat controlled by a single gene with only two alleles for that loci, the next generation will all have tails. It is likely that this is the case. Hope you like tails!

The tailless gene is dominant. Since your cat has a tail, it must have received recessive genes from its parents and cannot carry the tailless gene.

Why would you deliberately breed a non-pedigreed animal when the shelters are full of them? Even if your cat is half pedigreed Manx and half pedigreed Bengal, it is still a mutt cat and you cannot predict what they will look like, Mom, Dad, or a plain old mix.