DNA Opens Doors to War Dead Identities
By Douglas J. Gillert
American Forces Press Service
ROCKVILLE, Md., Jul. 13, 1998 It seemed like a grand idea: Locate letters sent by Americans from the Korean War and withdraw DNA from the saliva on the envelopes. Then, you could try to match the DNA with samples from recovered remains.
"We thought the stamps and envelopes would be a great source, because heres something the guy licked and sent to his mother or his wife," said Mitchell Holland, service laboratory chief with the Armed Forces DNA Identification Laboratory here. Its something that will have his DNA on it. But we started doing some studies and found that handling, contaminants in the mail, contaminants in the glue and the age of the specimen led to very unreliable results.
"Today, if you were to lick an envelope and send it through the mail, when we got it here, wed be able to [DNA] type you. Wed get a clean profile. But for 50-year-old envelopes, that doesnt work. "
Thats not to say that Korean War or much older remains cant be identified by their DNA. Although the most definitive DNA is found in the nucleus of human cells, DNA outside nuclei is more plentiful. Its this second type -- mitochondrial DNA -- that Holland and some 25 other scientists and lab and computer specialists use to identify human remains -- often with spectacular success.
"We work a couple dozen cases at a time and have provided matches on more than 100 cases," Holland said.
The laboratory needs two items to make identification: skeletal remains that provide a mitochondrial profile, and something to compare the profile to. He said the best comparisons can be made from known specimens from the deceased person -- specimens collected during a medical operation and stored in a hospital somewhere, for example, or even a lock of hair saved from the persons first haircut.
In the absence of such direct comparisons, researchers turn to maternal family members, because mitochondrial DNA is passed to descendants only through the female side. Any blood relative on the deceaseds maternal side of the family can provide a valid sample, including mother, siblings and grandmother. If the deceased is female, any offspring or descendants on her maternal side also can provide a valid sample.
Since 1991, the lab has worked hand-in-hand with the Armys Central Identification Laboratory in Honolulu, to identify the remains of Americans unaccounted for from the Vietnam War and earlier conflicts. As of this April, the lab had made 93 mitochondrial DNA matches: 72 cases from Southeast Asia, three from Korea, 15 from World War II -- and three from the Civil War.
After working in relative obscurity for years, the two labs gained broad public recognition this year when the family of Air Force 1st Lt. William Blassie suggested his remains were contained in the Tomb of the Unknown Soldier of the Vietnam War. Defense Secretary William Cohen directed disinterment and DNA identification of the remains, if possible. It took the DNA lab about one month to report back to Hawaii that DNA from the remains matched specimens provided by the Blassie family.
"This case has been a wonderful way to highlight the application of mitochondrial DNA to help identify these types of remains," Holland said. "Our goal is to bring these remains back to their families, and weve done that in so many, many cases. Because of its historical significance, the Blassie case brought us before the public eye, and weve been very positively received. Thats important, because this is really useful technology."