Wednesday, January 16, 2019


Are you factoring in the accumulating evidence?

The great preponderance of the genome is directions for making MOLECULES that create and operate the body.  We share the great preponderance of these genes with all preceding life because every new mutation or development includes what has gone before.  Have you read "Your Inner Fish"?

Whatever the proven genome may be at the moment, the environment can mute or unmute genes via a process called "methylation."  The methyl molecule adds itself to a gene because of environmental influences.  The earliest discoveries were due to food -- the period of starvation induced on the Dutch during WWII silenced certain genes for the next three generations and crossed gender lines.  This is called the epigenome. 

In another example a woman was discovered to have two completely different genomes in her body evidently because at a very early stage of gestation, her twin died (it was only a few cells at the time) and then mixed with the surviving fetus.  Such mixtures are called chimeras after a legendary composite animal that combined lion/goat/dragon.

Women who have had babies show that they have cells in their bodies with the baby's completely different genomes that evidently slipped through the umbilical cord and survived in the mother.

Did you know that sections of genes or individuals can move up and down the chromosomes, sliding along the helixes?  This is a chief means of new mutations and variation -- which is the definition of mutation -- which is the basis of evolution (not powerfulness) because it creates a range of characteristics, some of which fit the situation better than others so that those survive but the "others" do not.  The fittingness is the determinant.

So a rather blunt experiment done by scientists was simply counting the transpositions in eight different species.  "Using a bioinformatics comparative genomics approach, we performed analysis of species-specific mobile elements (SS-MEs) in eight primate genomes, which include human, chimpanzee, gorilla, orangutan, green monkey, crab-eating macaque, rhesus monkey, and baboon. These species have good representations for the top two primate families, Hominidae (great apes) and the Cercopithecidae (old world monkeys), for which draft genome sequences are available."  The result was that the crab-eating macaque had the fewest transpositions and was the least developed species and the humans had the most transportations.  Thus one could deduce that mutations created by sliding genes are the key to becoming higher animals.

Moving to the point of view of genomics, both through history and across continents, we find ourselves in quite different worlds where all the creatures that we learned about before we had words, expressing their identities by pointing in picture books and imitating the sounds we think they make -- we find their labels are unknown again.  If the species are not what we learned, if the world can be so transformed by new knowledge, how do we know how to act towards them?

At "23andMe". a genome-analyzing business, the questions are more personal.  Sibs turn out to have different fathers.  In a world where the Rule of Law controls ownership and inheritance and is based on genetic relationship, usually descent, the supposed accuracy of the evidence sometimes overwhelms family assumptions that have been convenient or even cherished.  At and other such businesses, special units have to be set up to help people handle the shock of reality.  Elizabeth Warren's political difficulties with her sentimental belief of Native American heritage are mild compared to people who discover their "family" is not their family. The story about the three identical pretty girls, triplets who turned out to have shared the same conception egg but have totally different heritages according to the tests, was highly entertaining.  Persons who sent samples to different companies and got quite different percentages had discovered that interpreting DNA is more an art than a science.

Legally, money and other entitlements can come or go. Fathers who used to be able to escape paying for a child's upbringing used to be able to claim that the woman had had many unions and it might not have been his contribution that started this baby.  Not any more.  One begins to understand why anal rape has become popular -- the fertility is not the kind that starts human gestation.
Measuring genetic linkage is done by "centimorgans", a unit of measurement based on genes shared.  Siblings normally share about 2,600 centimorgans of DNA, while half-siblings share 1,800.  That's only a premise and doesn't allow for mutations after birth-determined genes.

What do you say over the breakfast table?  What if a father knows he had a son with someone other than a legal wife, and the son was raised in that family but is told as a teenager who his "real" father is.  There is no word for this, not even a German composite like "doppelganger".  The realignment of one's identity narrative is major, possibly redemptive if it adds the right kind of parent, especially if the third figure is similar and supportive.  Our social ways of thinking about all this are as difficult to understand as when a gestating egg becomes a legal "person" or when a brain-destroyed person is actually dead.  What are the principles for thinking about this stuff?

The explanations for much of this stretch back in time through war, crime, generosity ("I have twins, please take one baby."), political deception ("Oh, your baby died. Also, we have sterilized you."), simple mistakes ("We'd better start marking these baby-mother  pairs with bracelets."), and surprise throw-backs when previously suppressed genes become dominant. ("Why is this baby BLACK?")   In my family it was red hair that suddenly appeared.

Since our society is so managed by stigma, which is mostly a matter of money and appearance, genetics deals a different hand of cards to everyone regardless of what they deserve. A chance moment deals the cards.  The suites of mix and match then depend upon the tension between genes and environment, which play off each other, producing quite different results.  Excellent genes still can be a death sentence.  Faulty or stigmatized genes can be rescued and even valorized by environment, either accidentally or on purpose.

We expect least that DNA is wandering molecules that can detach from any creature, as in the evidence in a rape kit or evidence left at a murder scene.  One person was convicted because the DNA of his cat had transferred to him and then to his victim.  Free-floating DNA is found in the sea, which is approximately where it evolved itself in the beginning.  They say that any two people who are physically intimate for whatever reason (caretaking, lovers) will soon share the tiny parasites in our guts and under our folds, each of which invisible beasts has independent microgenomes.

The impossibly long genomic threads of descent through animals might address history and give us evidence of appearance or qualities.  What if Elizabeth I was not the daughter of Henry VIII?  What if we had her genome and knew why she herself had no descendants?  Or that she wasn't "properly" female.  Such outrageousness can give us an appetite for revelations, which is probably as much a problem as taking genomes for granted.

If someone managed to find genetic evidence of Jesus, would he have triple helixes in all chromosomes and would the third one glow in the dark?  Tri-somal conceptions -- humans with three wound-together helixes of genes -- cannot live.  You've got to pay attention and you might not like the evidence.  You might realize you made some of it up.

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