A British father suspected of abducting Madeleine McCann hopes he will be cleared after the DNA sample from a possible kidnapper was recovered from the bedroom of the Algarve holiday apartment where she disappeared 30 days ago.

The first forensic science evidence that a stranger had been in the bedroom where Madeleine was kidnapped emerged as her parents said that her disappearance may be linked to other child abductions in Portugal and Spain.

Forensic scientists have been unable to find any DNA linking the abduction to Robert Murat, the only official suspect in the investigation. He hopes to receive official notification within days that he is no longer under suspicion.

Details of the mysterious DNA sample found in Madeleine’s bedroom will be sent to detectives in Britain for checks against convicted or suspected sex offenders. There is no national DNA database in Portugal.

The Instituto Nacional de Medicina Legal (INML) has already compared the unidentified DNA sample with Madeleine’s parents, Kate and Gerry and her two-year-old twin sister and brother, Amelie and Sean, who were asleep in the same room at the time of her disappearance.

The DNA evidence was formally delivered to the police on Friday by Professor Francisco Cortareal, who has been leading a team of scientists analyzing material from the McCann apartment and a nearby villa where Murat lives with his mother.

Duarte Nuno Vieira, president of the INML, confirmed that the first DNA samples had been handed to Policia Judiciaria but refused to comment on the reports that evidence had been found that a stranger had been in Madeleine’s bedroom.

“We still have a number of samples to process so the work will continue next week. We will try to do it as quickly as possible,” he said.

A source at the forensic science institute told 24 Hours newspaper: “There is DNA which does not correspond to the family. It is an important step in the investigation but the truth is that the DNA collected does not have a "name."

“In other words, we can not make any connection between the material collected and the suspects we actually have. The evidence is very vague and doesn’t serve to sustain the accusations against the only arquido (official suspect) which exists in the case.

“This does not mean that Robert Murat can not be incriminated but there is a person in the room which it is, as yet, not possible to identify.”

Murat, 33, has been the only official suspect in the case for more than two weeks after the police searched his villa which is less than 100 meters from the McCann apartment.

He had returned to Portugal after visiting his estranged wife and their three-year-old daughter in Hockering, Norfolk, just three days before Madeleine’s abduction.

Tuck Price, who is acting as spokesman for Murat, said: “Robert has not heard from the police for a week and a half. We expect the police to write to him and tell him he is no longer a suspect and that he is a free man. Then he can clear his name.”

Under Portuguese law, police can keep Murat as an “arquido” for eight months, during which time he is forbidden from talking about the investigation under strict rules of judicial secrecy.

Price said: “Robert knows he will only be cleared properly when Madeleine is found and the people who took her are caught. This is a small town and there will always be whispers until the police catch the people who did this. Then he can get on with his life again.”

One theory being investigated by Portuguese police is that Madeleine was abducted by an international paedophile ring which could have taken her to another country in Europe or North Africa.

Gerry McCann said Friday that his daughter’s disappearance should be examined in connection with other abductions, particularly in neighbouring Spain, and that there should be a European-wide response to child abductions.

“I would like some reassurance in Spain that there has been some proactive investigation regarding Madeleine’s disappearance,” he said.

“I think it is at least worth exploring the possibility that Madeleine’s disappearance should not be considered in isolation, so putting it into context with other disappearances in the Iberian peninsula, even the Canary Isles as well.

“We do feel that perhaps these types of disappearances should be considered in a pan-European fashion, the same way that other EU movement of people is considered.”

Meanwhile, his wife acknowledged publicly for the first time that Madeleine could have been taken by a pedophile.

“It is a more upsetting scenario that any other. We have considered all scenarios as everyone has,” she said. “We have no evidence to suggest that there has been any harm to Madeleine, that she is not alive and well.”

However, both parents said they still hope her abductor is someone who wanted a daughter of their own and would never harm her.

The couple, from Rothley in Leicestershire, urged anyone holding her to leave in a safe place where she can be easily found.

Gerry McCann, a consultant cardiologist, said: “We pray that she is being looked after and it is someone who wanted a little girl for their own who would look after her very well. We also pray that the person who has her gives her up voluntarily and drops her at a church or a safe place.”