Scientific Technique Focusing on DNA Aids British Police : ‘Genetic Fingerprints’ May Catch Killer

Police investigating the murders of two teen-age girls near this small Midlands village are applying a new scientific technique that some predict could be the most significant breakthrough in resolving serious crime since fingerprinting was invented.

The technique involves isolating elements of the genetic structure in blood, a structure that scientists say is as individually distinctive as a fingerprint. It has enabled Leicestershire County Police investigators to confirm their initial belief that the same man raped and strangled the two 15-year-old schoolgirls, Lynda Mann and Dawn Ashworth, even though 2 1/2 years separated their deaths.

The test also led directly to the release of a 17-year-old youth who had been formally charged with one of the murders.

Now, police hope to positively identify the killer by collecting blood and saliva samples from every male between the ages 13 and 30 who lives or works in the area of three villages that surround the grasslands where the girls were attacked.

“It’s technically difficult to do, but it has enormous potential,” said Dr. Kevin Kelly, a University of Aberdeen biochemist who has performed the test and recently co-authored an article on the subject. “It’s a breakthrough.”

The voluntary testing program, which might have aroused strong controversy over constitutional and privacy issues in the United States, has been met with relatively little opposition here. This rural but close-knit society has been so shocked and frightened by the murders that peer pressure has overcome what little reluctance there has been to cooperate with the police.

Some civil libertarians, however, have voiced reservations about the technique.

Peter Thornton, a courtroom lawyer and a spokesman for the National Council for Civil Liberties, expressed concern, both about possible human error in conducting the complicated test and the implications of mass screening for a criminal such as that now under way here.

“Police have treated these volunteers like murder suspects, asking them for a photo or whether they have a criminal record,” Thornton said. “At the very least we need Home Office guidelines or a (special) committee of Parliament to look at the implications of this test.”

Thornton did concede that “very positive benefits” could come from the test, such as resolving paternity disputes or determining parenthood in immigration cases, “as long as there are proper controls on its use.”

The technique was first developed by Leicester University geneticist Alec Jeffreys in a laboratory only a few miles from the murder scenes. It focuses on material called DNA, deoxyribonucleic acid, found in the chromosomes of all living beings. Chromosomes contain an individual’s basic blueprint, determining everything from sex to eye color.

Specifically Arranged

According to Jeffreys, the series of bands that make up the DNA are arranged as specifically and individually as a fingerprint, a similarity that has given his technique the name “genetic fingerprinting.”

The test can be effectively done on dried blood as much as three to five years old or on dried semen up to three years old, Jeffreys said.

The chances of two people having the same DNA fingerprint are estimated at about 30 billion to one. Genetic fingerprints of parents and children are said to be similar, but not identical.

Although they are individually specific, however, Jeffreys stressed that DNA fingerprints contain no information regarding the sex or even the species of the donor.

“If you took samples from half a dozen gorillas and half a dozen people, you couldn’t tell them apart,” he said. “They’d just be a series of lines on an X-ray.”

The technique has yet to be challenged in court, but the British Home Office has already accepted genetic fingerprinting results as evidence in a limited number of immigration cases where proof of parent-child relationship was required.

“The test is clearly of evidential value,” a Home Office spokesman said.

More traditional tests, such as blood typing, already are routinely used to eliminate suspects from criminal investigations, but are much less exacting and therefore unsuited for positive identification.

The British chemical company Imperial Chemical Industries, which bought global rights to the genetic fingerprinting test, is building a special laboratory at Abingdon, near Oxford, to conduct tests commercially.

Possibly Knew Victim

The decision to do a mass sampling in the Leicestershire villages is based on evidence indicating that the murderer knew both the area and possibly his first victim.

“From all we’ve looked at, we strongly believe the culprit is a local man,” Detective Supt. Anthony Painter, the senior investigator in charge of both cases, stated.

Because of evidence indicating that the attacker may have been a school acquaintance, police have set a relatively low age cutoff of 30.

Painter said this still means that between 4,000 and 5,000 men are being asked to voluntarily give blood and saliva samples in order to clear themselves. After two months, he said, 2,880 samples have been taken. This figure includes all but 22 male residents of the three villages. None of the 22 are resisters but were merely away for such reasons as military duty or vacations.

Testing has since started on those who work in or near the villages, including employees of a psychiatric hospital.

Some of the qualms voiced by Thornton were echoed by the group of young men at the Enderby village school one recent evening as they waited to give blood and saliva samples.

Before giving blood, each man presented proof of identification and was asked to sign a form acknowledging that he was aware of the nature of the test and its voluntary nature.

Coaxed Him to Go

Martin Lardner, a 24-year-old mechanic, had not kept his original appointment because he felt the tests were an invasion of his personal privacy. But family and friends coaxed him to go, noting that his own sister could be the murderer’s next victim.

“They saw my point of view, but no one wants to let the killer get away,” he said, shrugging.

A 27-year-old medical student, Hugh Turner, believes the tests were basically “the right thing to do” but complained how a telephone call from a police detective had upset his mother.

“She didn’t know what it was about, and she got worried,” he said. “If there’s another murder next year, are they going to go through this all again?”

Painter said only a dozen men had so far told the police that they would not submit to the test but that in each instance, they changed their minds after talking with detectives.

“Some said they didn’t like needles; one said he didn’t like cops,” Painter noted. “But we haven’t had a single instance where the reluctant ones haven’t come around.”

In a county of 835,000 people that considers 1986, with five homicides, a bad year for crime, the vicious rape and murder of two personable local girls has had a stunning impact.

Atypical Social Pressure

Those who know the area say the horror of the crimes and the strong sense of community outrage among the close-knit middle-class villagers have generated atypical social pressure on those with reservations about giving the samples. After all, locals point out, life cannot return to normal until the killer is caught.

“There is serious apprehension in those villages,” said Lawrie Simpkin, executive editor of the Leicester Mercury, the largest-circulation evening newspaper in the county. “You won’t see girls walking around after dark alone, and if a lad went into a village pub and announced he was refusing to take the blood test, he’d be on the local ‘s--- list,’ that’s for certain.”

Such factors have helped to make the test locally acceptable. “It’s not a program you could carry out in an inner-city area,” summed up Painter.

Although the local population has been generally receptive to the tests, a blanket public awareness program, including saturation media coverage, also preceded the testing.

Each household in Enderby plus the neighboring villages of Narborough and Littlethorpe were visited in the weeks after each murder. Then, last December, uniformed officers personally distributed to each home a four-page Leicester Mercury “murder special,” which detailed the crimes and appealed to the public for help.

Local television and radio also dwelt on the murders.

As the first step in organizing the genetic test samples, Painter wrote a single-page letter that appealed to a sense of civic responsibility, called for cooperation and stressed that the tests were voluntary.

The letters also contained an appointment time.

Those who failed to keep their appointment quickly received either a telephone call or in-person visit. Those who provide samples eventually receive a note of thanks, telling them that they have been cleared.

Over Half Negative

According to senior Leicestershire officers, over half the samples are found negative through routine testing at a regional forensic laboratory near Cambridge. The rest are sent to the Home Office Forensic Science Service laboratory at Aldermaston, 60 miles west of London, for genetic fingerprinting tests that can take up to eight weeks.

According to police figures, roughly 900 people have been positively eliminated from the investigation so far.

Painter said that about 60 officers are working on the two cases and that the 2,880 samples taken so far represent roughly 20 times the number sent by the county’s police force for forensic tests in the course of a normal year.

Results of the complete testing program could take up to nine months to receive, he estimated.

He admitted that the high level of resources devoted to the investigation is only possible because of the crimes’ social impact.

“There aren’t many murders in Leicestershire,” he said. “These are high-profile crimes. It’s important for us and important for the community that they are resolved.”