They were born 1,000 miles apart, in Britain and Finland. Now two four-year-old boys have discovered they share a sperm-donor father.

When Sally, 43, gave birth to her son Alex, she knew only that his father was Danish and was a good footballer with blue eyes and a talent for jazz piano.

He was identified by the alias “Jens” and by his sperm sample number, 3001, from the Cryos clinic in Denmark.

"Alex has become the first child to be put in touch with a half-brother or half-sister by a US-based website, the Donor Sibling Registry, whose parents have agreed to go public.

In total, 17 British children are in touch with half-brothers or sisters through the website but they have chosen to remain anonymous at the moment."

After posting details on the site, Sally was contacted by Riikka Turunen, a graphic designer from Helsinki, Finland. Turunen had used sperm from the same donor to conceive her baby boy, Kasper, who was born in August 2004, just six weeks after Alex.

The mothers now regularly chat by e-mail and swap photographs of the boys, and they are planning to meet.

The case raises questions in Britain about whether children should have the right from birth to know they have been conceived with donor eggs or sperm and to be told the identity of their genetic parents.

Children born since April 1, 2005, are entitled to be told the identities of their genetic parents when they reach the age of 18, although, unless their parents tell them they were conceived with donor sperm they would remain ignorant of their origins. The rule also applies to foreign sperm used in British clinics.

Alex was born in Warwick before the law came into force, and recipients of donated sperm such as Sally have no right to know who the donor is.

Peers including Lord Alton, who campaigns on fertility issues, and Baroness Deech, former chairwoman of the Human Fertilisation and Embryology Authority, have called on the government to require birth certificates to state when a child has been conceived via a donor.

Sally, a marketing manager who does not wish to disclose her surname, set out to trace her son’s brothers and sisters through the Donor Sibling Registry website because she wanted Alex to know more about his genetic background.

Fourteen British children conceived via donors have so far contacted each other through the registry and 111 British families are using it to look for relations.

Sally, who has dual British and Australian nationality and has moved to Melbourne, said: “Out of the blue, I got an e-mail from this person in Finland saying, ‘I have just noticed your information on the website. Are you absolutely sure your donor was number 3001 from Cryos because we have a son born from the same donor?’”

Satu Sorjonen, 44, Turunen’s civil partner, who helps to raise Kasper, said: “We read in a newspaper about the registry and we were curious to see if we could find any matches.

“It was a nice surprise. My first thought was, ‘I hope he is not someone we already know’, because that would have been quite awkward, but it was very nice to find Sally and Alex.”

Sally underwent fertility treatment, using donated sperm, at the private Midland Fertility Services clinic at the age of 38.

Gillian Lockwood, medical director of the Midland clinic, believes the rules in Britain should change so children can be told the identity of their donor parent before they are 18.

Although Sally was living in Britain, she bought the sperm through the US office of the Danish sperm bank, because more details of the donor could be disclosed in America.

“If my son became a good pianist, I could say: ‘You get that from your donor father.’ I wanted to be forearmed,” she

said. Sally has examined photographs of her son’s half-brother for traits inherited from their father. “I think there are similarities in the mouth and chin,” she added.

The two families are considering meeting in four years, when the boys will be eight.

Sally insists, however, it will be up to the boys how much contact they have with their half-brothers. “Alex is interested in football and I told him his donor father was good at it. I am also introducing him to more about Kasper,” she said.

Sally believes that, with the information she has, and with the help of friends in Denmark, she could identify “Jens”.

She would not, however, invade his privacy if he did not wish to be contacted. Danish donors still have the right to remain anonymous.

Ole Schou, founder of Cryos, warned that if other families were less willing to respect the anonymity of genetic parents, this could deter potential donors. “I can see a big problem if this continues,” said Schou. “The donors maybe will find themselves on the internet.

“If five or six characteristics are listed, there will be only one donor in the world who will match this information. These donors may be trying to protect their own families.

“We need to deal with this or we will lose donors.”

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