We all get our genes from our parents and pass them onto to
our children. Over thousands of years
the genes mutate and leave distinct genetic markers. Humans beings evolved in Africa and migrated out of Africa to
populate the Earth. This took many
generations to accomplish and over this period the genes passed on from one
generation to the next gradually mutated leaving genetic markers among
populations that settled along the way.
Therefore it is possible to analysis the genes of populations and use
the information to track their long term history back to Africa.
There is one type of DNA which is passed from father to son
and another type (mitochondrial DNA) that is passed from mother to child.
When tracked all the way back mitochondrial DNA (mtDNA)
leads back to one woman who, remarkably, all the people alive today are
descended from. This doesn’t mean that
she was the only woman alive at this time, it just means that all the other
women around at the time had their mtDNA gradually filtered out by only having
boys or not having any children. To
give you an example. When the
descendents of the Bounty were finally discovered after 25 years on Pitcairn
Island most of them had the surname Christian.
That doesn’t mean that Fletcher Christian was the only man who settled
on the island. It just means that some
people hadn’t had children and some had only girls so the variation in surnames
gradually diminished. It’s the same
with mtDNA.
In our case, Mary, Teresa and Kathleen Dagleish all got
their mtDNA from their mum, Helena Chapman, and passed it onto all their
children. This is the mt DNA which
grandma got from Mary Stephenson who got it from Mary Elizabeth Dean who got it
from Elizabeth born in Salford, who got it from her mum. Sarah, Anne-Marie, Rachel, Ruth and myself
have all passed it onto our children, and so will Helen if she has any. Amy, Helena, Abigail and Phoebe will pass it
onto their children but Michael, Leo, Ben, Joe and Sam will not.
National Geographic are running a project called the
Genographic Project which examines the DNA of those who take part, like
me. To look at the results log onto
https://genographic.nationalgeographic.com/genographic/lan/en/journey.html
and enter the genographic ID number FWGPAUBJ6R
It gives a map showing the route our female ancestral line
has taken out of Africa and talks about the history of the haplogroup that we
belong to, which is K. There are also
explanations of mtDNA which are likely to be clearer than mine above!
Back to Helena
Chapman’s family tree