What are dapple gray horses?

No. Dapple grays aren't born dapple, they get dapples as they grow older. Most dapple grays were grey/white when they were born.

Dapples are a color variation most commonly seen on grey horses. They are circular in shape and will usually fade as the horse grows older to a more uniform grey color.

A dappled horse is like a horse with patches or spots of colour on it. Some horses are just brown, grey, black etc, dapple is just another colour variation. The horse would usually be white with grey...

Dapple grey is a colour. Horses are born with it. Nothing causes it. However, they can loose their dapples and get whiter with age.

White horses are called gray because underneath all that white fur, their skin is grey/black. NOT pink.