Albinism
An inherited inability to make melanin leads to albinism, where skin, eyes and hair are pale. It is generally a recessive condition. Mutation in several genes can compromise melanin production, including 'OCA2'. Albinism is also a feature of some rare syndromes, such as Hermansky-Pudlak syndrome, which have a much wider range of symptoms.
People with albinism often have eye problems and are at high risk of skin cancer in hot countries. They have also suffered social stigmatism. The condition has often been associated with antisocial tendencies in film and literature - the National Organization for Albinism and Hypopigmentation (NOAH) has identified 68 films made between 1960 and 2006 that feature an 'evil albino' character.
Silas, in Dan Brown's 'The Da Vinci Code' (2003) (played by Paul Bettany in the 2006 film version), is a religious fanatic and an assassin who murders several people. Although criticised for this portrayal, Brown has argued that Silas's behaviour is a result of his treatment by others rather than his skin colour and illustrates “how cruelly societies can ostracize those of us who look different".
'The Twins', computer-generated killers played by Adrian and Neil Rayment in 'The Matrix Reloaded' (2003), were widely considered to be inspired by albinism (an accusation denied by the film's producers).
Positive role models comprise several musicians including Yellowman from Jamaica and Malian Salif Keita, as well as Connie Chiu, a model who works with Jean-Paul Gaultier.
Albinism is seen in animal species (including many laboratory species). A sensitive portrayal of an albino animal is seen in 'Sophie and the Albino Camel' and other books by Stephen Davies. The books' hero is a cheerful and generous albino camel called Chobbal, who is looked after by a young African boy after being rejected by his mother.
Possibly the most notable albino animal was the sperm whale Mocha Dick, immortalised by Herman Melville as Moby Dick (though the fictional animal had only a white hump). From 1810 until 1859, the white whale survived some 100 battles with whalers off the coast of South America, wreaking terrible damage on ships that challenged him (though appearing docile and companionable when left alone).
Image: Zulu Albino; Wellcome Library, London