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Scientists identify DNA in ancient human brain
( 2003-05-17 14:15 ) (8)

Chinese scientists announced earlier this week they had successfully extracted DNA from the brain of an ancient female corpse dating back more than 2,000 years.

Scientists with Jilin University in northeast China have finished five months of research and claimed it as a first for Chinese scientists to extract DNA from the brain of an ancient human.

The female corpse was excavated from the Laoshan Han Tomb of the Han Dynasty (206 BC-AD 220) on Beijing's western outskirts in August 2000.

During the excavation of the tomb, scientists happened to save one piece of "dried mud" the size of a fist, which dropped from the skull of the female tomb occupant.

Using three-dimensional technology, physical anthropology and DNA technology, paleontologists with the frontier archeology center of Jilin University and Beijing Research Institute of Cultural Heritage worked together to discover clues to the blood relationship of aristocracy of the Han Dynasty.

"DNA study shows the empress of the feudal prince of the Western Han Dynasty, who was about 30 years old, belonged to the Mongoloid race in east Asia. The result accords with conclusions made with 3D technology and physical anthropology," said Zhu Hong, director of the frontier archeology study center with Jilin University.

The research had provided a new study method in molecular biology study to extract DNA from brain remnants, said Pan Qifeng, a paleontologist with the Chinese Academy of Social Sciences.

Usually ancient brain tissue could only be dehydrated and kept in a special environment and could be rarely found in archeological field work, said Professor Zhu Hong. "I had never met brain tissue of an ancient human in my 20 years of archeological work, though I had studied thousands of corpses of ancient humans," Zhu said.

"It's lucky that scientists extracted DNA from the brain, though they failed to obtain DNA from bones or teeth," said Professor Zhou Hui, director of the archeological DNA laboratory of Jilin University.

Equipped with China's first professional DNA research laboratory, the frontier archeology research center of Jilin University has set up a DNA database on ancient humans and successfully finished DNA study of bones of ancient humans found in the Xinjiang Uygur Autonomous Region, Inner Mongolia Autonomous Region and Qinghai Province.

Archeological DNA study could help build a gene database of ancient humans and explain human evolution and migration, said Zhu Hong.