lots of stuff under culture> discrimination. Most of it is pretty mild or anecdotal, but I thought this one was pretty interesting:

In September 2011, Cryos International, one of the world's largest sperm banks, announced that it would no longer accept donations from red-haired men due to low demand from women seeking artificial insemination.

E: also -

In Medieval Italy and Spain, red hair was associated with the heretical nature of Jews and their rejection of Jesus, and thus Judas Iscariot was commonly depicted as red-haired in Italian and Spanish art.

The medieval prejudice against red-hair may have derived from the Ancient biblical tradition, in relation to biblical figures such as Esau and King David. The Ancient historian Josephus would mistranslate the Hebrew Torah to describe the more positive figure of King David as 'golden haired', in contrast to the negative figure of Esau, even though the original Hebrew Torah implies that both King David and Esau had 'fiery red hair'.