re Wizarding Genetics

[Catlady (Rita Prince Winston)]

No: HPFGUIDX 183676

HP Fan 2008 wrote in
<http://groups.yahoo.com/group/HPforGrownups/message/183621>:

<< Ordinarily, a child gets the magical status from the mother - hence
the children of a witch mother will usually be magical, and the
children of a muggle mother will usually be a muggle. >>

I agree that the children of a witch mother will be magical if the
father has any magic genes at all (unless the child has the Squib
syndrome). As I wrote << The presence of magic selects for magical
genes. A witch mother will bear only wizarding children with her Mm
mate, because her womb will select the m sperm -- where could there be
more magic than inside the body of a magical person? >>

It seems that the wizarding folk do not agree that the child of a
Muggle mother and a wizard father will usually be a Muggle, because
they say 'Half-blood' rather than something like for Mumdim or Nomaff
for 'Mum uses magic, Dad is Muggle" or 'No Magic Father'.

Of course, the children of wizard father, muggle mother of whom the
wizarding folk know would be the ones I described as << the Mm mother
who lives surrounded by magical people, such as her mate, in a house
held up by magic, will also be influenced to produce m eggs. >> They
wouldn't know the children of the Muggle woman who conceived during a
one-week romance with a stranger, whom she didn't know was a wizard,
while on holiday in a foreign country. After that one week, her
exposure to magic is so limited that it would taken some *very* heavy
gene combinations for her child to develope magic. And if that
happened, the wizarding folk, not knowing who the father was, would
assume the child was a complete Muggle-born.

<< In addition to the question of having magic, there may also be the
question of the magic being strong enough to be noticeable. Some
"squibs" may actually be wizards or witches who actually are magical,
but the magic is so weak that it can't be used. >>

That's a good point. We'd have to invent a reason WHY it's so weak,
because it appears that Squibs can be born to two magically strong
parents as well as to two magically weak parents.

<< Such people may also be born to muggle families - I believe that
the mother of the Creevey brothers may be such, explaining why both
brothers are wizards. >>

My idea was that, in addition to both Creevey parents being Mm, there
was a wizarding family living in the house next door, thus exposing
Muggle Mrs Creevey to magic.

Bruce Alan Wilson wrote in
<http://groups.yahoo.com/group/HPforGrownups/message/183590>:

<< Anent wizardling genetics, I've always thought that there wasn't a
single gene, but a set of genes.

1. The gene or genes that allows one to sense magical energies;
2. The gene or genes that allows one to manipulate them;
3. The gene or genes that account for specialized magical abilities,
like metamophomagus, animagus, seer, etc.

(snip) Squibs may have 1, 2, 3, or 1 & 3. >>

I've always believed that Squibs, having two wizarding parents, have
the normal supply of wizarding genes. Their lack of magic power COULD
be due to a rare double-recessive anti-magic gene, but I doubt it. I
think it is due to pre-natal or peri-natal environmental factors, and
therefore a Squib could have fully magical children, and OUGHT to be
considered a pureblood by the bloodists.

<< Those who leave the wizardling world and marry into Muggle families
may pass them on; there are probably any number of Muggles wandering
around carrying partial magical genes, but until/unless they unite
with another such, they won't produce a Muggleborn wizard. >>

Yes. I believe the heterozygous Muggle must unite with another
heterozygous Muggle AND some exposure to magic during pregnancy to
produce a Muggleborn. Not necessarily direct exposure, but living on
the same block as a witch or wizard or powerful magical artifact would
suffice. (I typo'ed 'artifcat' and decided that a pet half-Kneezle
would suffice.)

<< ("Magesport" is the term I use for such.) >>

Such what? Muggleborn wizards? Their parents?

**** Elaboration on "peri-natal environmental influence' on Squibs and
Muggleborns

My theory has a subset which can be rejected without rejecting the
rest of the theory, that there is a set number of people in this world
with wizarding powers. The magic behaves as if it has certain amount
of will of its own and upon the death of a wizarding person, it goes
to a suitable new-born person. The suitability of the new-born person
depends first on genetics and how much magic affected those genes
prenatally, second on how much magic is already around the new-born
person, third on how near in space and time the birth is to the death. 

Thus, a Squib is a child who was born with all the genes and pre-natal
and peri-natal exposure to magic to be wizarding, but no wizard died
close enough around the time they were born.

And a Muggleborn is born when a wizarding person died and no wizarding
child was born around that time. 

'Around' is a loose term: it could be that a wizard died and his magic
went to a Muggleborn that day, and the next day a wizarding child was
born and didn't get magic until another wizarding person died a year
later. But a wizarding child born during that year would be closer in
time and get the magic and leave the first hypothetical a Squib. (And
giving a millimeter of truth to the evil government's claim that
Muggleborns had stolen their magic from a wizarding person.)

I like this sub-theory for its irony that Voldemort's war against
wizards who didn't want to exterminate Muggleborns resulted in killing
many pure-, full-, and half-blood wizarding folk whose magic went, on
their deaths, to create an unusually large number of Muggleborns.
(Because wizarding folk, other than Molly and Arthur, were having the
same or fewer children than usual during the dangerous war times.)

Then any 'baby boom' at the end of the Voldemort war (births would
outnumber deaths) would result in an unusually high number of Squibs.
I think the usual number of Squibs is one or two per generation.

*** One thing this sub-theory needs is a reason why the number of
people with wizarding magic, after growing along with the rest of the
human population for many many millennia, would suddenly become fixed
at a certain number.