White tigers lack which pigment that normally gives orange fur?

White tigers lack pheomelanin, the pigment that normally gives their fur its orange coloration.

Pheomelanin produces reddish, yellowish, and orange tones in mammalian hair. In white tigers, a recessive genetic variant interferes with pheomelanin expression, so the orange background of the usual Bengal-tiger coat is replaced by white. Eumelanin, which produces dark brown and black tones, remains sufficiently active to form the tiger’s characteristic dark stripes.

This is why a white tiger is not a true albino. Albinism generally involves a much broader reduction or absence of melanin and often affects eye pigmentation. White tigers retain dark striping and colored eyes, even though their overall coat is pale.

White tigers were documented in India for centuries, and the captive population became strongly associated with Mohan, a white tiger captured in 1951 in the former Rewa state. Intensive breeding for the recessive coat trait has raised concerns about inbreeding and associated health problems. The coloration is a genetic variant, not evidence that white tigers belong to a separate species.