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.
"Despite the proof of its prevalence, there is some kind of unanimous censorship exerted over the discussion of albinism in Aicuña," writes Dr. Eduardo Castilla, who studied the genetic structure of Aicuña. "The world albino is rarely spoken aloud, as if it were a taboo, one of those dark family secrets that can be ignored if no one speaks of it."
So, too, discovered photographer Guidotti in 1997, when his encounter with the stunning 13-year-old motivated him to highlight the beauty of albinism in his own work. Frustrated with public perceptions, he contacted the National Organization for Albinism and Hypopigmentation (NOAH).
"At first, they told me to get lost," he said. "They thought I was a little crazy because I was so excited and so upset with what I saw. There was the fear of exploitation. Every time there is a story about albinism, they are a victim."
After some persuading, NOAH has embraced Guidotti's concept and used his photography to portray "the world of beauty in albinism" as a way to fight stereotyping. Today, Guidotti's nonprofit organization -- The Positive Exposure -- is devoted to that goal.
Indeed, NOAH president Michael McGovern said his organization, which focuses on education and research, struggles to get out accurate information.
"People may go through their whole life and not encounter a person with albinism," he told ABCNEWS.com. "They can be as unreal or as fictitious to them as a unicorn."
Just this week, Samwel Mluge, secretary general of the Tanzanian Albino Association, attended NOAH's annual conference in Las Vegas, where participants will seek to create a world alliance in the fight against stereotypes.
Guidotti's imagery has been the centerpiece of much of that effort.
"We will solidify a lot of other organizations," Guidotti said. "It will be the mothership of all groups worldwide. In higher numbers we are more powerful. I don't have albinism but I feel a part of that community."
The organization has been particularly concerned about negative images of albinism in Hollywood and sought, unsuccessfully, to encourage director Ron Howard to remove the murderous albino monk from the 2006 film "The Da Vinci Code."
The caricature of the "evil albino" has become a "silver screen staple," according to the Web site Skinema. From Chevy Chase's sinister sniper in the 1978 film "Foul Play" to nasty characters in "Matrix Reloaded" and "Princess Bride," albinism is portrayed in a dark light.
The site, run by San Francisco dermatologist Dr. Vail Reese, claims that two dozen blood-thirsty characters have appeared in movies from 2000 to 2003.
"We're not saying that they're not ever going to be bad but just once it should be a good guy," said McGowan, who knows first-hand the pain of stereotypes.
One of seven children, McGowan was born with albinism. Neither of his parents nor his siblings had the trait. Because it is an autosomal recessive condition, families can be "carriers" yet not outwardly display its traits. Two carriers have a one in four chance of having a child with albinism, which is rooted in the latin word meaning white.
Albinism is a "genetic dice game," according to McGowan, now 50. Nearly all experience uncorrectable low vision and in some cases Hermansky-Pudlak Syndrome, a sometimes fatal condition that causes bleeding, colitis and, in the most severe cases, pulmonary fibrosis.
Like others with albinism, McGowan does not see life in "detail" because the optic nerve connections are misrouted in the brain. "I can see it's a car driving down the street and can't read the license plate or see the face of the driver."
McGowan's parents were accepting and he was educated in mainstream classrooms. But many with albinism are relegated to special classes or schools for the blind, which does more harm than good, he said.
"If you limit highly functioning kids and put them in with kids who are much more visually impaired, it lowers the horizon and bar for where they can go," said McGowan."
McGowan was teased as a child, and even today, as director of electronic information in the Chicago court system, he has incidents.
"I am a middle-aged guy in a corporate business suit and briefcase and I walk a half mile home," he said. "I get 100 feet past the bar and some goofball yells out at the bar at the top of his lungs, 'Hey, albino.' He'd probably been drinking all day but it hadn't happened since I was an adolescent."
Because albinism crosses all races, discrimination is not limited to random jeering, McGowan said.
"When bleached-out kids are born to families that are Mediterranean, Hispanic, Asian or African-American, sometimes there is ignorance and a question of lineage -- 'that isn't my baby,'" McGowan said. "There are also extreme cases of rejection."
McGowan and Guidotti see imagery as one vehicle for overcoming the demoralizing myths of albinism -- prejudice that arises from the same ignorance about all human differences.
When Guidotti first began working with NOAH, he met Chrystine, a 5-foot- 8-inch tall teen with albinism. She was later part of a photo spread in Life magazine.
"She was so beautiful, but her shoulders were hunched, her head was down and she made no eye contact," he said. "She'd been tortured and teased her whole life and had no self-esteem."
By the time the studio music got going and the camera lights were flashing, Chrystine began to see herself "for the first time" as a beautiful girl, Guidotti said.
"She left kissing everyone on their cheeks," he said. "Right before my eyes she was transformed, and I understood in that moment I was a new advocate and ambassador for change."
Today, Chrystine works with special needs children on a farm in Oregon. "Chrystine is so much more than her albinism," Guidotti said.
With a friend, Guidotti later received a Cornell University Medical School fellowship to study cultural perceptions of people with albinism in the South Pacific. Today, his photography is recognized worldwide.
"It's a metaphor for all differences," he said. "We are the same and we are all different in our sameness."
Click here to view Positive Exposure photographs.