It was at the corner of Park Avenue and 20th Street in New York City that fashion photographer Rick Guidotti first spotted a pale, teenage beauty with snowy hair.
"She had long gorgeous hair and giggled with her friends, and she had zero pigmentation," said Guidotti, who had shot on runways around the world for Revlon, Elle, Marie Claire and St. Laurent.
Despite years of casting and international shoots, by the mid-1990s Guidotti had never worked with a model with albinism.
"I was always told who was beautiful and forced to work within the parameters of beauty -- this model, this season and this face," Guidotti told ABCNEWS.com. "My own ideas of beauty were completely ignored."
Struck by the stranger's unusual but striking features, Guidotti went home and poured through medical journals to learn more about people who've traditionally been called albinos.
"All I kept seeing were pictures of people in underwear, lining against the walls in doctors' offices with black bars across their face," he said. "They were all sad and dreary, images of despair."
Increasingly referred to as "people with albinism," they were once portrayed in circus sideshows as oddities associated with superstition and magical powers.
But today, in a growing movement -- fueled by atrocities in Tanzania and ordinary discrimination worldwide -- advocacy groups seek to dispel the myths and remove the social stigma associated with a form of hypopigmentary congenital disorder that afflicts an estimated 18,000 people in the United States.
In Tanzania -- where albinism occurs at rates as high as 1 in 3,000 births -- people have been slaughtered by witch doctors for their organs, which are considered lucky and used in magic potions. Rapes also have been reported in Zimbabwe, where many believe that having sexual intercourse with a person with albinism can cure HIV/AIDS.
Even in the United States, children of all races with albinism face ignorance and discrimination because of their unusual coloring.
According to the National Institutes of Health, albinism occurs when one of several genetic defects prevents the body from making melanin, the substance that gives color to hair, skin and the iris of the eye. In the United States, it affects 1 in 17,000 (about 1 in 20,000 worldwide) .
In its most severe form, oculocutaneous albinism, the hereditary condition causes white hair and skin, and pale eyes -- usually blue or violet -- that have untreatable visual problems.
As early as 1857, Phineas T. Barnum thrilled curiosity seekers with a Dutch family with albinism who were part of his traveling circus. Even more ghoulish were the Lucasie sisters, billed as black Madagascans with pink eyes that stayed open while they slept.
In more modern times, several notable musicians put a positive face on albinism: blues guitarists Johnny and Edgar Winter and Jamaican reggae singer Winston "King Yellowman" Foster. Before his local success and U.S. breakthrough in early 1980s, Foster had been shunned as cursed and sent to live in an orphanage.
From the white whale Moby Dick in Herman Melville's classic novel to modern urban legends of "albino colonies" in the rural Pine Barrens of New Jersey, albinism has more often than not been associated with evil.
Because albinism is caused by two recessive genes, it is seen in higher numbers in societies that are isolated or where there is intermarriage. In one remote community -- Aicuña, Argentina -- the rate of albinism is 1 in 90.