A forensic genetics expert says trying to establish the identity of the severed head found at Mepal quarry will be extremely difficult if police have no leads to go on.

Cambs Times: Mick George Quarry Block Fen Mepal. Picture: Steve Williams.Mick George Quarry Block Fen Mepal. Picture: Steve Williams. (Image: Archant)

On Bank Holiday Monday it will be a fortnight since the head was found by a workman inside a skip yet still police have not been able to confirm if it was male or female or how old they were.

Dr William H Goodwin, reader in forensic genetics at the University of Central Lancashire, Preston, said: “In cases like this it is extremely difficult.

“If you have a presumed identity you can run checks against their dental records

“But if you have no presumed identity it is not easy,” he said.

Cambs Times: Mick George Quarry Block Fen Mepal. Picture: Steve Williams.Mick George Quarry Block Fen Mepal. Picture: Steve Williams. (Image: Archant)

Working out the age of a person is possible up to the mid 20s but once the skull sutures have fused upon maturity it becomes tricky to work out the difference between a person in their 20s and a person in, for example, their 40s, he said.

Likewise, ethnic origin can only be distinguished to a certain degree.

“You can tell the difference between a white Caucasian and a SE Asian but you cannot easily tell the difference between a white Caucasian and a person of Bangladeshi origin,” he said.

Standard DNA profile results take two to three weeks but even then, without a presumed identity, trying to track down the person who met their end so brutally is difficult without any firm leads.

Cambs Times: Mick George Quarry Block Fen Mepal. Picture: Steve Williams.Mick George Quarry Block Fen Mepal. Picture: Steve Williams. (Image: Archant)

Teeth are the best place to take DNA, he said, but there is no national register to run those against - you can only check if you have a presumed identity.

DNA can also be taken from bone.

The DNA results can be run through the police database but that will only be successful if the person has been arrested for a criminal offence.

“You can look to landmarks, for example, ridges on the eye brows or there is a spot on the back of the head that is more prominent in males,” Dr Goodwin said.

Cambs Times: Mick George Quarry, Block Fen, Mepal, where a human head was found on Monday May 16. Picture: Steve Williams.Mick George Quarry, Block Fen, Mepal, where a human head was found on Monday May 16. Picture: Steve Williams. (Image: Archant)

But he added: “There is a very limited scope of what you can do with genetics or anthropology.”

So far a post mortem has proved inconclusive in determining whether the head, found by a workmen at Mick George Ltd, was male or female.

A police spokesman said: “We are waiting on DNA testing results.

“We continue to work with specialists to establish the gender and identity of the deceased.”

Searches at the quarry have been completed and a scene is no longer on at the Sharnbrook site in Bedfordshire.

The spokesman said: “We are working with the British Transport Police to conduct searches of the railway line.”

Police are not ruling out that it could have been a suicide on the railway tracks.

“That could well be one theory,” said the police spokesman.

“Unfortunately at this stage we are not able to narrow it down and specify the type of inquiry.

“It could be murder, it could be suicide or an accident such as being hit by a train, but we are keeping an open mind.”

A post mortem concluded the person died at least 17 months ago - before January 1 2015.

It is understood the head came from a site in Bedfordshire 40 miles away which is owned by train company Network Rail and is currently at the centre of a building project.

Debris was taken from the site in a skip to the Mepal quarry and the head was somehow amongst it.