for National Geographic News
The oldest intact human mummy, the Iceman, comes from a genetic line that has either died off or become extremely rare, according to a new DNA study.
The latter study involved samples from his intestines that also included his DNA.
New analysis of a mere 0.002 ounces (70 milligrams) of this intestinal material has allowed scientists for the first time to sequence Ötzi's complete mitochondrial DNA.
Mitochondrial DNA is passed from mothers to their offspring, and although it can accumulate mutations, part of it usually remains unchanged, making it useful for tracing lineage through mothers.
(Learn about DNA.)
Mutations in Ötzi's mitochondrial DNA formed "a unique subcluster within a known European lineage," said lead author Franco Rollo of the University of Camerino in Italy.
However, the Iceman's line became, "if not extinguished, extremely rare" during the last 5,000 years, Rollo said.
The research was published online today in the journal Current Biology.
Ötzi possessed the oldest modern human mitochondrial genome produced so far, noted co-author Martin Richards of the University of Leeds in the U.K.
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