Longahair is determined by this gene.
There are no difference between the
gene which gives the longhair in the Persian and in Semi-longhair cats.
The difference between the differen type of longhair is in the structuer of
the fur.
Shorthair dominates over longhair.
[LL] is shorthair
[Ll] and [L-] is shorthair variants
[ll] is longhair.