Advanced DNA testing helping police make new gains in solving cold cases:scientist

Some of those advances, and how they're being used, aren't quite so dramatic.

Sometimes they simply help police and relatives answer lingering questions about what happened to loved ones who mysteriously disappeared.

RCMP in Alberta are crediting an advanced test, called mitochondrial DNA, for helping to solve a 17-year-old mystery.

Sgt. Patrick Webb said earlier this year they used the test to positively identify human remains found near the Bow River west of Calgary back in 2003.

Investigators had a report from June 1, 1991, about a man whose family says was swept downstream when he tried to swim the river.

But the remains they'd discovered were covered with dirt, and they thought they were too far from the river bank to be those of the missing man, Lambert Daniels, 23.

In February, an RCMP investigator casting a fresh set of eyes on the cold case pushed for advance DNA testing after hitting on a new theory.

"When she looked at it, she determined that due to flooding, the river could actually could have been up to that level (where the bones were found). At that time, it deserved a second look," said Webb in an interview Thursday from his Calgary office.

With a blood sample from the missing man's brother and DNA taken from some of the bones that were found, investigators recently got a positive identification 17 years after Daniels disappeared.

Police say the sophisticated test has brought some answers to the man's family, and some satisfaction to investigators.

Pernell Daniels, 43, credits the persistence of that RCMP officer, and technology for helping to bring some closure to his family over the death of his younger brother.

"All these years, it's been a very long struggle. Even looking at the river sometimes doesn't feel right," he said in an interview from a Calgary funeral home, where he was making arrangements for his brother's funeral on Monday.

"I guess I am glad that they have this kind of technology now," he said.

He added that sadly, his only sister and father died before such tests made the identification possible.

Looking at mitochondrial DNA is a much more successful test when trying to match old remains, said Arlene Lahti, a senior scientist at Molecular World, a Thunder Bay, Ont., genetics lab that helped to crack the cold case in Alberta.

According to the company's website, it's one of the only facilities in the country accredited by the Standards Council of Canada to do all types of genetic testing.

Bone samples and found human remains are often decayed, exposed to bad weather, gnawed by rodents and exposed to bacteria and fungus, which makes the other two genetic testing methods extremely difficult, Lahti said.

"At the end of all that process, the DNA remaining inside the bone samples themselves is in very poor shape and it makes it very difficult to retrieve any DNA out of it," she said.

Because mitochondrial DNA is passed down only through mothers, scientists can use samples from blood or cheek swabs from siblings or other close relatives to confirm identities.

"For instance, if we have some found human remains and we develop a mitochondrial DNA type from there, we can now compare that type to suspected brothers or sisters of that individual, we can also look at mothers and aunts or female cousins along that line," she said.

"That's very useful, because it can be very difficult to track down relatives and get DNA to have some comparisons to do. Without the relatives, we can't make any identifications at all," Lahti added.

Mitochondria, which Lahti described as the "power plant" that provides the energy for cells to function, occur in every cell. Many cells have only a single mitochondrion, whereas others can contain several thousand.

Because they exist in such high numbers, scientists have a high success rate of grabbing mitochondrial DNA and making matches, even from degraded remains.

Other types of tests rely on much less genetic material, so over time, it degrades so much that it becomes much more difficult to get a good sample to help confirm identities, Lahti said.

"You could use mitochondrial DNA on a brand new sample like a blood stain...or a hair sample or you could use it on very, very old degraded samples like skeletal remains, teeth, even shed hairs from very cold crime scenes," she said.

This type of test is being used to help identify three victims in one of the worst mass murder cases in U.S. history.

Twenty-seven people, all between 13 and 21, were dug from shallow graves near Houston and areas of East Texas in the early 1970s.

The identities of three boys have remained a mystery, until a mitochondrial DNA test done on the refrigerated corpses last year helped give the local medical examiner's office a lead on the identity of at least one.

In late May, Lenore McNiel and Donna Lovrek submitted samples of DNA to compare with the unidentified victims and are still awaiting the results.

They wonder if their brother, Randell Lee Harvey, 15, was among those who were brutally murdered by Dean Corll and his two teenage accomplices, Elmer Wayne Henley and David Owen Brooks 35 years ago.