Paleoanthropology,
genealogy and the miracle of DNA
Part Three
William
Hudson. Latest update 7th May 2012
In order to
understand the types of issues that DNA analysis can help resolve, it’s worth reviewing,
at least qualitatively, a few well-known examples.
Mitochondrial
DNA examples
The last Russian royal family
In 1991,
nine bodies were exhumed from a shallow grave just outside Ekaterinburg on the
eastern slopes of the Ural Mountains in Russia.
Circumstantial evidence, along with mitochondrial DNA sequencing, provided
a compelling argument that the remains were those of the Romanovs, the Russian royal
family who were executed in 1918. Tsarina Alexandra, the three children buried
with her and Prince Philip's (her great nephew) mitochondrial DNA turned out to
be an exact match on 740 tested nucleotides. Three years later, additional DNA evidence was
obtained from the Grand Duke Georgij Romanov (the 28-year-old brother of Tsar
Nicholas II, who died of tuberculosis in 1899) that confirmed this theory.
Two
children were absent from the 1991 grave site. A second grave was discovered close-by
in 2007. Combined mitochondrial DNA, autosomal STR and Y- STR testing on those
remains provided evidence that the two individuals recovered from the this
grave were the two missing children of the Romanov family: the Tsarevich Alexei
and one of his sisters.
Cheddar Man
In 1903, human
remains were found in a cave in Cheddar, England. They were those of a 23
year-old man who was determined to be about 9,000 years old. Ninety-four years
after the discovery of "Cheddar Man", Oxford University scientists
were able to extract mitochondrial DNA from his tooth cavity. The Oxford team then
distributed DNA test kits to Cheddar schools and a close match was found to a
local schoolteacher, Adrian Targett. He lives half a mile from the burial site
and is a history teacher. Two exact genetic
matches were identified with local school children whose identities remained confidential
to this day.
“Oetzi" the Iceman
“Oetzi"
the Iceman was found in 1991 in the Italian Alps. He lived in the Neolithic era,
about 5300 years ago and is now on display at the South Tyrol Museum of
Archaeology in Bolzano, northern Italy. DNA testing shows that Oetzi belongs to the K1
subcluster of the mitochondrial haplogroup K which suggests he is most closely
related to southern Europeans, possibly with populations of Sardinia and
Corsica. However, it is believed that he has no living descendants.
Titanic baby
The body of
this child was found floating in the North Atlantic, six days after the famous cruise
liner sank. The original DNA test conducted in 2002 identified the baby as Eino
Panula by matching his DNA to that of living family members in Finland. However
subsequent mitochondria tests confirmed that the baby was not related to the
Panulas but was, in fact, Sidney Leslie Goodwin who was on the cruise liner
with the rest of his British family at the time of the disaster.
Guilty or Innocent?
Hawley
Crippen was an American doctor who moved to England in 1900 with his wife,
Cora. After Cora disappeared in 1910, police found mutilated remains beneath
the cellar floor in Crippen's home and which were determined to be hers. Crippen
was convicted of Cora’s murder and hanged at Pentonville Prison. He protested
his innocence to the end. In 2007, a team of forensic scientists from Michigan
State University compared mitochondrial DNA from remains kept at the Royal
London Hospital Archives with samples taken from Cora’s surviving relatives. They concluded that remains could not be those
of Cora Crippen and that, in fact, they were from a male victim. Even though MSU’s
conclusions have been challenged, Hawley Crippen’s family has launched a legal
battle to clear his name.
Y-chromosome
DNA examples
Did Thomas Jefferson father children
by his slave, Sally Hemmings?
Thomas
Jefferson is widely believed to have fathered at least some of the children of
his slave, Sally Hemmings. To resolve these long-standing claims, a DNA study carried out in 1998, found
a direct Y-chromosome match between male-line descendants of Field Jefferson
(Thomas Jefferson's uncle; Jefferson himself
had no male descendants of his own) and a descendant of Sally’s last son, Eston
Hemmings and confirmed that they share a common Jefferson ancestor. The Thomas
Jefferson Foundation believes that the known evidence (including the DNA
results) indicates a high probability that Jefferson was indeed the father of all
six of Sally Hemings's children listed in the Monticello records. However, the Thomas Jefferson Heritage
Society reached different conclusions and suggests that Jefferson's younger
brother Randolph was more likely the father of at least some of Sally Heming’s
children.
Genghis Khan
Genghis Khan's
empire extended across Asia from the Pacific Ocean to the Caspian Sea. A group
of geneticists studying Y-chromosome data found that nearly eight percent of
the men living in the region of this former Mongol empire carry y-chromosomes
that are nearly identical. That translates to roughly 16 million descendants
living today and it is postulated that Genghis Khan was their common ancestor. The
connection to him will, however, never be a certainty unless his grave is found
and his own DNA could be extracted.
The Lost Tribe of Israel?
The Center
for Genetic Anthropology at University College London set up a project to examine
the Bantu-speaking Lemba tribe’s oral tradition of Jewish descent. Today, they are found in Zimbabwe and South
Africa. The team collected DNA samples from African Bantus, Yemeni Arabs and
Sephardic & Azhkenazi Jews to compare the amount of similarity that existed
between each of these groups and in particular a particular series of genetic
markers on the Y chromosome of Lemba males. The study did suggest that the
Lemba, and more specifically members of the Buba sub-clan, seem to have an
ancestral connection to the Judaic populations that were tested.
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