Uncertain Health in
an Insecure World – 35
“Y-Chromosome Adam… Meet Mitochondrial Eve”
All males have a ZFY
locus on their Y-chromosome that is made up of 729 identical base pairs. To
scientists, this sameness suggests that all men alive today are descended from
a single man… Let’s call him Adam. And because the Y-chromosome
is passed directly from fathers to sons, genealogists are able to trace male
ancestry back to the evolutionary beginning of humankind.
On the other hand, mitochondrial DNA is passed down from
mothers to both daughters and sons. As originally described in a 1987 Nature paper, mitochondria DNA is
simpler, comprising some 37 genes as compared to nuclear DNA which contains
>70,000 genes. Because mitochondrial DNA is conserved across generations but
(almost) never comes from the father, scientists believe that every living
person has the same ancestral mother – Let’s call her Eve.
Fascinating stuff!
But what does this mean to developed world Ancestry.com buffs seeks their genetic
roots using DNA assays?
While our common >200,000 year remote Old Earth ancestors
may have lived in east Africa without producing progeny, Adam and Eve were the
first to pass their DNA on to children who became Young Earth humanoids. This
longer Y-chromosomal DNA lineage may explain why modern male descendants of
Adam wait longer for their haplotype DNA roots than do female descendants of
Eve.
Unlike geographic mapping, geneography is not this simple.
Over nearly three decades since, the uniformity of the maternal
mitochondrial Eve story, as attractive as it was then, has been scientifically
assailed and eventually disproven to some persons’ thinking. Mitochondrial DNA mutations and
recombinations are now known to exist, and paternal passage is possible.
In addition, DNA testing introduced by Google-backed 23andMe in 2007 came under extreme regulatory
scrutiny in 2013 in the U.K. and the U.S for health risk profiling claims based
on genetic traits. But perhaps knowing why you cannot smell asparagus in your
urine, whether you will sneeze looking at bright sunlight or whether your
earwax is dry aren’t crucial personalized health determinants. For just US$99
and a little of your spit, you are also giving these big data analytic giants
the rights to connect your private personal data and genetic details… Whoops!
The perilous journey begun >150,000 years ago by Adam and
Eve’s DNA continues today.
For the first time in evolution, in the last decade (that’s
0.00667% of human history), mankind has unlocked the capacity to connect our
individual ancestries to our genetically-predicted health futures.
This is both exciting and dangerous. This is also fraught
with the potential for global public good, and bad.
We in the Square are agnostic on Ancestry.com, but big believers in the capacity of DNA data analytics
to Match.com our descendants’ DNA to
their health futures.
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