Jim Butcher never explains how exactly magic is done. All he did was show that it conformed to some rules of physics.

But I'd be interested to see just how scientifically accurate the idea of magic only being able to be passed on by females...

 

Well, from my really basic understanding of genetic, if the "magical gene" (even if it can be more than one gene that give the ability to use magic, we will keep it simple) is on the segment of the sexual chromosome "X" that is not shared with the sexual chromosome "Y", than it will be mainly passed on by female.

If the "magical gene" is dominant, a wizard who marries a woman without the "magical gene" will have a daughter with magic, but all his sons will be normal. If the gene is recessive, none of his children will be able to use magic, but his daughters will be carrier of the gene


If he marries a woman that is a carrier of the "magical gene" (one magical gene): if the gene is dominant (the mother would be a witch), all his daughters will be able to use magic and 50% of his son may be able to use magic. If the gene is recessive (the mother is not a witch), 50% of his sons or daughters may be able to use magic.

If he marry a full witch (two magical genes), all their children will be able use magic.

Of course, I am only speaking in terms of statistic. It is not scientifically wrong, in that case, to think that magic is mainly transmitted through the maternal line. However, it's a little idealistic to think that one gene can decide if someone will be a wizard in the Dresden Files, because of all the possible manifestations that magic has and the divergent level of power. And we must not forget that others thing than genetic influence magic in Butcher's Universe, like the planets alignment that gave Harry his power over the outsiders.

 

Or the fact that

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Charity's genes went from magic genes went from dominant to recessive/nonexistent from not using her powers.

 

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I don't agree with your affirmation.

If the “magical gene” gives you the ability (potential) to use magic, not using it doesn't influence the dominance or recessive character of the gene. I see it more like a muscle that gets atrophied from not being used. You still have the muscle, you just can't use it.

If she really wanted, I'm sure that Charity could use magic. It would be hard, but she still has the potential.

 

You're missing the point.

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The point was that, by 'giving up' magic, any kids she had after that point wouldn't be magical.

 

You may be right, so

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I suppose that Molly is not her daughter, since none of her children can have magic following that logic.

 

You know what's really weird?

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I was about to make the same argument, only with Amanda, before I remembered that that's not Dresden canon, it's Shezzaverse.

Now I feel like rereading the Denarian series...

 

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She gave up magic after Molly's conception. This isn't even up for debate, as it has been said multiple times by Butcher.

 

Molly was the first child, conceived not long after Charity met Michael.

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(and therefore not long after she stopped using her powers) The most likely implication is that she was still sufficiently magical at that point to pass it on to her offspring. By the time the other kids came along, she would have then been magically barren.

second edit: ninja'd, drat

 

Why? No one - not even Rowling herself - claimed that the magic gene was on the X-chromosome, or the Y-chromosome, or any particular chromosome. She only said that there is A gene that grants the carrier the ability to do magic; and, that muggleborns have a magical ancestor.

The theory I laid out simply corrected for the Rowling's stated notion that the magic gene is dominant - it can't be because otherwise non-magical muggles would then be a tiny minority in comparison to billions of wizards and witches. The fact that the magical population has always been relatively small in comparison to that of the muggles' indicates that rather than dominant, the magic gene is recessive.

If, however, the genetics of magic were more like the genetics of eye color, then it is entirely possible that some people are just magically more powerful than others - or even more capable of some schools of magic than others: charms vs. transfiguration vs. dark magic. Eye color is not determined by a single gene, but by a number of them, which means that you could have the genes m1, M1, m2, M2, ... m#, M#. That means you could have some squib mutation genes but enough non-squib magic genes to still be able to perform magic - at this point, the entire mess becomes altogether too complex.

The genetics of magic have nothing to do with magic itself - it's just one more gene determining some particular trait some person might have - no different from the gene(s) that let one person roll their tongue and another person wriggle their ears.

EDIT: I don't mind non-genetic explanations for why someone might be magical or not - gift from God/the gods, magical artifact, pregnant woman was around a bunch of magical shit radiating magical auras into her womb, whatever. However, if the author is going to claim a genetic origin of the ability to do magic, they should at the very least get the very basic facts right and springboard from the implications of those basic facts.

Rowling, not I, claimed a genetic origin of magic. Rowling made squibs. Rowling made absurdly small numbers of wizards in a world with 6.5 billion people in it. Rowling claimed that muggleborns had magical ancestors. And it was Rowling who claimed that the magic gene is dominant. All of these but the last are explainable with a single, recessive gene, but not with a dominant gene.

 

I'm pretty sure he's referring to the Dresden Files, not HP in that post.

Scribblerus, I'm 99% sure he's discussed it on his forum before. Something about magic being based on environmental factors in the womb. Like...if the mother has magic, the fetus is constantly being exposed to it, and will therefore be capable of using magic. If the mother is non-magical, but is being exposed to magic very often, the same would apply.

 

Yeah . . . I was wondering why the conversation took a sudden turn for the what-in-the-fuck-are-you-people-talking-about?

 

Well, in the post you quoted, he did mention Jim Butcher by name. That should've been an indicator.

 

I'd think the reason why it's highly dominant, yet only a minority of the world's population have the gene is because of the wizarding world's seclusion from the Muggle population. As the Pureblood population mostly marries between themselves, and are obviously the majority in Magical culture, it seems to be reasonable that there would be so few Wizards.

If the wizarding world was to come out into mainstream society, it would also be reasonable to assume that the wizarding gene would grow exponentially throughout the next generations until it was as common as having a type of hair color.

And it's clear that Squibs and Muggles, based off of Rowling's interviews, are essentially the same thing: the only difference being parentage. Neither can perform or react to magic like any wizard or witch. Thinking about Filch, a Squib would not fall for a Muggle-repelling charm only if they knew the magic was there.

It's like Stan Shunpike said, "Don' listen properly, do they? Don' look properly either. Never notice nuffink, they don't."

If they knew it was there, they'd be able to look past the magic I'd think, much like a notice-me-not charm.