Re Potterverse: Social Psychology - Wizarding Genetics--Revisiting Genetics

Mon Jul 1 20:26:00 UTC 2002

No: HPFGUIDX 40672

Alexander Lomski hypothesized, some time ago..

>Genetic Theory

>We make an initial assumption that magical talent is
>controlled by some gene or set of genes. In other words, we
>assume that wizards do have no differences from muggles but
>in their genetic code.

>So far, so good. What genes, then?

I concur, but your analysis seems to be based predominately
on Mendelian Genetic theory and does not take into account
some of the more recent advances in the understanding of
the molecular basis on the gene and research into certain genes
that causes disease.  While we always start with the obvious genes
(why is he the one that got sick) most mechanisms seen in genes
that cause disease-causing mutations occur throughout the genome.

Having spent *way* too much time studying genetics as I squandered
my youth as a perpetual student I have some ideas to add to the mix.

>First of all, we can reasonably assume that Wizarding Gene
>(called WG in the text) is the dominant. This conclusion
>springs immediately from the statistics of wizard-muggle
>marriages: so far no wizard born from a muggle and a wizard
>has reported to have non-magical brothers and sisters.

Here I agree, but am changing nomenclature just a bit.
W is someone with the dominant wizarding allele
w is someone with the recessive non-wizarding allele
(allele is one of a number of types that any gene can be found
in)  which matches genetic nomenclature better.  Esp.
since genes are more likely to be named for what the 
"mutant" expression rather than the wild-type. 

I propose that one main gene controls magical Vs non-magical.
Other genes may influence an individual's magical talent (are
they better at charms, etc) but I think my theory may shed some
light on how a single gene could cause the variety of magical
talent we see in the Wizarding World.

>Second, magical talent is controlled not by a single pair
>of chromosomes (like gender), but by a set of them. This
>conclusion we draw from the facts that: a) wizards sometimes
>appear in completely non-magical families, and b) single
>dominant gene would manifest itself in one of the parents at
>least.
>Also we must remember about Creavey Case. In a non-magical
>family both children were born with magical talent. We can
>reasonably assume that both Creavey parents have parts of
>the magical genes set heterotyped (doubled). From this we
>can also expect most of Creavey children to posess magical
>talent. If this conclusion will be supported by long-term
>research, this will become a significant proof of the
>theory.

Ah, but we have examples of new mutations arising in genes
that cause dominate diseases (Huntington's for example) there
are a number of genetic diseases that arise from a particular 
mechanism.  They share the traits that they arise spontaneously
"out of nowhere" in previously unaffected families.  Although one
tendency that we don't have data on, that occurs in the diseases,
but may or may not occur in wizarding folk is that as the generations
pass the disease seems to affect the descendants more strongly.

The underlying mechanism for these "new mutants" has to do with
the fact that many genes in the human genome have long stretches
of repeated DNA.  Now these long stretches of repeated DNA are 
variable sometimes even from generation to generation.  My proposal
is that some repeated stretch...

(hmmm lets see we got A's and C's and T's and G's to make repeats
out of...CATCATCAT would be almost too much to hope for, but I am sure
some other strangely appropriate repeat will be found to be the basis
of the repeat...I suspect someone with more wit than I possess will be
able to conjure up a much more wildly appropriate repeat.)

...of DNA lies in the w allele and when it becomes long enough a W allele
is produced.   

This could account for the reports of Muggle-Born Wizards.  Every so often
in somemuggle's gametes while being copied the gene gets longer, probably
considerably longer.  This child now carries, and passes on the longer repeat
and magical ability.

It could also  be that once we genotype enough wizards we 
may find that one hypothesis of mine is true.  That the # of repeats
has some bearing on the general level of talent someone has, even
if it is not the case that each generation gets stronger, as we see in
diseases.  

And there should be some upper limit to the # of repeats with something 
that is way too long being non-viable.

>Another conclusion is that if some muggle family has a
>wizarding child, we can expect them to have partial magical
>parentage themselves, if often lost in the ages.

Which is not necessary with my theory.

>About rarity of squibs.

>So far we know that Wizarding World experiences a large
>amount of muggle-blood injections. This probably has some
>connection with the fact that magican genetic patterns have
>certain influence on either reproduction abilities or
>behavioral patterns (more probably former). Hence we can
>assume a relatively large percent of muggle genes in the
>Wizarding World genetic pool. Even with dominant magical
>genes we should expect a relatively large percent of squibs.
>But this doesn't seem to be the case.

>This can only happen if whole genetic pattern is not
>required for a child to be magically talented. That is, even
>a part of magical genes is enough. Whether this means that
>the child is less talented or powerful or it's not the case
>should be researched further.

In most cases where these repeated stretches of DNA cause 
mutations we find that it is quite rare for a gene once it is 
elongated past a certain threshold to become significantly 
shorter in the descendants.  So it could be that once w becomes
W then there is little ability for it to revert on it's own.  Reversion
could happen on occasion and cause the rare squib to show up.

However, given the number of heterozygous wizards running
around (half-bloods) it seems odd that squibs rarely occur as
there should be a significant number of w genes hidden in 
the wizarding population.

This leads us to need research in just how the W gene effects
other things.  One suspicion is that it can either out-compete
gametes carrying the w gene (since wizards have unusual 
resiliency maybe this is seen on the cellular level) or that the
eggs of wizard woman because of cytoplasmic differences 
almost only accept W carrying sperm.

Another thing seen in the genetic world is that for some genes
(not that well known in humans, but widespread) if the Mother
has one version of the gene she almost never carries an
offspring of the other genotype.

But I suspect some sort of Non-Mendalian explanation will be
found to explain why the recessive w allele doesn't show up more
frequently than it does given the extent of cross-breeding reported.

And it may be that the W allele in and of itself has magical ability and
it directly alters any w allele it finds itself with.  Taking the selfish gene
theory to the ultimate limit.

Ksnidget--don't even get me started on palindromic mutational theory.....