British detectives have been asked to investigate the backgrounds of Kate and Gerry McCann.

Police in Strathclyde are to dig into the couple's university days 20 years ago and contact former friends and colleagues from their time in Scotland, where they first met.

Detectives in Portugal hope the probe might uncover something in the McCanns' past which could shed light on the case, the Sunday Mirror reported.

The request - made via Europol - was part of the root-and-branch review of the case ordered by its new head, Paulo Rebelo, and the first interviews could be carried out next week.

Strathclyde police refused to comment but a source told the newspaper: 'It's a back-to-basics check. We've been asked to trawl the backgrounds of the McCanns to build up a full picture of their lives right back to university.

'It is a full check on their lives to see exactly what type of people they are.'

Mrs McCann was nicknamed 'Hot Lips Healy' during her student days at Dundee University, according to her year book.

Kate Healy, as she was then, was one of the most popular students in the medical department, where classmates said the Liverpudlian loved parties and trips to the pub, but still passed all her exams with ease.

Her year book entry read: 'Renowned for frequently indulging in alcoholic binges and "dance till you drop" nocturnal activities, she immediately led the rest of her fellow colleagues astray.

'Hot Lips Healy maintained a consistent Friday night appearance in the Union throughout the whole of first year.'

Mr McCann, the son of an Irish-born joiner, studied at Glasgow University and moved out of his parents' tenement flat in Govanhill to share a flat with five friends.

The couple met in Glasgow's Western Infirmary in 1992 after finishing their medical degrees, but did not begin dating until 1996. They married in Liverpool in 1998.