WHEN Koreen McQuilton was thumbing through profiles of anonymous sperm donors at a California fertility institute 20 years ago, she never imagined that one day she and her daughter would be meeting the man whose sperm eventually made her pregnant in 1987.

On a sunny Los Angeles morning last Monday, McQuilton and her 19-year-old daughter Ryann waited nervously on the campus of the University of Southern California for the arrival of Jeffrey Harrison, a 50-year-old drifter who had suddenly come forward to acknowledge genetic paternity of at least half a dozen children born with the help of the California Cryobank’s donor No 150.

“I got this call on Saturday night,” said Wendy Kramer, who operates a website devoted to helping the children of sperm donors trace their genetic siblings. “This guy kind of hemmed and hawed, and then he said, ‘Well, my name is Jeffrey, and I’m donor 150.’ He caught me off-guard, and my response was: no s***.”

It was perhaps the most remarkable breakthrough in the short but inspirational history of the Donor Sibling Registry (DSR), a unique online network of children conceived with donated sperm. For more than a year, Ryann McQuilton and at least six other children of donor 150 had been searching for their genetic father.

Their quest had attracted international attention, as the first generation of offspring from a new kind of American family struggled with heartrending issues of identity and parenthood.

“I had always known that even if we found our donor dad, there was a high chance he might not want contact,” Ryann McQuilton said last week in her first media interview since meeting Harrison. “But once it was him that came forward first, I felt so much more positive and confident.”

For Koreen McQuilton, a Mas-sachusetts school administrator who by chance had been visiting Ryann in Los Angeles when Harrison emerged last weekend, it was a bittersweet moment for her daughter and a more complicated harking back to a different time in her life, when she and her lesbian then-lover were seeking a sperm donor to help them begin a family.

Mother and daughter were driving through Los Angeles when Ryann’s mobile phone rang. It was Danielle Pagano, a New York teenager who had also been conceived with donor 150 sperm and who had met Ryann through the DSR.

“She was yelling, ‘Our dad contacted Wendy, our dad contacted Wendy’,” Ryann said. “I couldn’t really understand what she was saying. Then Wendy called me, and there was never any doubt in my mind. I definitely wanted to meet him.”

For Harrison there was a potentially embarrassing problem. On his donor’s profile form he had described himself in glowing terms — he had a philosophy degree from Europe, he was a dancer, a musician, a fitness instructor and a writer. He also claimed to play water polo and said he loved animals and children.

Yet 20 years later, donor 150 did not boast quite so appealing a resumé. He has no full-time job, no permanent home, and lives alone with his four dogs in a van parked near the beach in the bohemian suburb of Venice.

“You have to remember that these donors were just regular guys,” said Kramer. In the 1980s, many donors were down-and-outs who needed the $100 (£51) or so the clinics paid for each batch of sperm. Coming forward years later to meet the children they fathered has in some cases proved to be awkward.

“Yes, they are nervous,” Kramer said. “They are thinking, ‘What if the kid is very, very smart and I’m not that smart? Whatever expectations the child has, what if I don’t meet them?’”

Koreen McQuilton remembers looking through the profiles for evidence of intellectual accomplishment — Harrison’s philosophy degree sounded encouraging — but in the end, she said, she was more concerned by health and other genetic issues.

“Reading those profiles was really like going through a catalogue, and the choice did feel a little bit random to me,” she said.

“Some of the other parents had different reasons for choosing No 150, but for me it was like, well, he seems okay. And now none of that really matters.”

It certainly does not matter to Ryann, a second-year communications student, who was not upset to discover her genetic father was living in a van.

“I don’t live a very conventional lifestyle myself,” she said. “I grew up with two moms, and his lifestyle doesn’t bother me at all. When I met him we automatically felt a connection to each other. He’s a really great guy.”

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