Like their brethren around the world, these people have complicated, often sorrowful, stories. They have been cast out by their families and fired from their jobs. They have struggled to find love.
Martin, who became a man six years ago, proposed marriage to the woman he'd loved ever since they were classmates.
"She said, 'Yes, I love you, I understand you, but I don't know about my parents,' " says Martin, who has a prospering business importing vitamins from Russia.
When the couple approached the woman's parents, they were flatly rejected. "They think I'm a lesbian," Martin says. "They said, 'We won't give our daughter to a girl.' Especially her mother, she was very hard with me." His heart was broken, and the relationship faded.
When Dr. Bahrom Mir-Djalali first began performing sex-change operations 15 years ago, he endured death threats from scandalized parents. One father, he recalls, showed him a dagger and vowed to slash his throat. But slowly, he says, society has come around. He measures the shift in the fights with the families, which he says have become less drastic.
"This is an Islamic country, and very, very old-fashioned," says Mir-Djalali, a white-haired surgeon who studied sex-change procedures in Paris. "I try to tell people, 'They don't have horns, they are normal people.' But it's hard for society to accept. At least now we have a discussion about it."
Iran isn't the only Muslim society that appears to be growing more accepting of sex changes while still shunning homosexuality. A Kuwaiti court recently decreed that a 29-year-old man who had changed his gender could live legally as a woman. That decision was later overturned by a higher court, but it provoked a startling debate in a country where the subject of homosexuality remains taboo.
In Saudi Arabia, an Islamic judge backed an heir's right to keep the larger share of inheritance given to sons even though the heir had undergone surgery to become a woman. Even Al Azhar, the ancient seat of Sunni Muslim learning in Cairo, issued a fatwa, or religious edict, in the mid-1990s that approved gender changes in some cases.
But no Muslim society has tackled the question with the open-mindedness of Shiite Iran. That's probably because the father of the revolution himself, Ayatollah Ruhollah Khomeini, penned the groundbreaking fatwas that approved gender reassignment four decades ago.