Of all the half-Muggles in JKR work, what is the percentage of those with muggle mother vs father?

Question

As part of my digging into heritability of magic, I am trying to see if there's any difference between the chances of being a wizard with one Muggle parent if your mother vs. your father was a Muggle.

As far as I know, JKR didn't cover that explicitly, but we can at least make a guess based on statistics.

As such: Of all the half-Muggles mentioned by JKR (books, supplemental books, interviews, Pottermore) where we know who was a Muggle among parents, how many were Muggle fathers vs Muggle mothers?

To avoid creating an endless list of answers, if you can think of another example that wasn't tallied before, please edit it into an existing answer.

_{NOTE: this question uses "half-Muggles" instead of JKR's term "half-blood" because I only care about kids whose one parent was a Muggle; whereas in Potterverse, the "half-blood" term also applies to those whose second parent was Muggle-born magic user (such as Harry Potter).}

Answer 1

Working from the list presented on the HP Wiki (I know it’s not canon, but I have sources!), we can split the magical folk who are half-Muggles into two lists.

Muggle father

• Seamus Finnigan. As he tells us at his first Feast:

  “I’m half and half,” said Seamus. “Me dad’s a Muggle. Mam didn’t tell him she was a witch ’til after they were married. Bit of a nasty shock for him.”

  — Philosopher’s Stone, chapter 7 (The Sorting Hat)

• Gilderoy Lockhart. This comes from Pottermore:

  Born to a witch mother and a Muggle father, with two older sisters, Gilderoy Lockhart was the only one of his parents’ three children to show magical ability.

  Of note: he had two sisters who turned out to be Muggles. We don’t know about siblings for most people listed, but I'll include them at the end.

• Minerva McGonagall. We learn from Pottermore that she was half-blood, with magic coming from her mother’s side:

  Minerva McGonagall was the first child, and only daughter, of a Scottish Presbyterian minister and a Hogwarts-educated witch.

  She also had two brothers who turned out to have magical abilities:

  Two more children, both sons, were born to the McGonagalls, and both, in due course, revealed magical ability.

• Tom Riddle. As is well-documented in the books, his father was a Muggle of the same name, whom he hated and murdered. Magic came entirely from his mother.

• Severus Snape. We learn from his memories that his mother was a witch:

  “You are,” said Snape to Lily. “You are a witch. I’ve been watching you for a while. But there’s nothing wrong with that. My mum’s one, and I’m a wizard.”

  — Deathly Hallows, chapter 33 (The Prince’s Tale)

  His half-blood status is confirmed by the moniker he chose as a child.

• Bowman Wright. He has a Famous Wizard Card which confirms his parentage:

  Mother was a witch, and father was a Muggle.

  His full entry can be read in the list of Famous Wizard Cards from the HP Lexicon.

Muggle mother

• Remus Lupin. Again from his Pottermore entry:

  Remus Lupin was the only child of the wizard Lyall Lupin and his Muggle wife Hope Howell.

• Dean Thomas. Although his father walked out on his mother when Dean was very young, he eventually realises that his father was a wizard. Alternatively, we could read J.K. Rowling’s old website:

  When the letter came from Hogwarts Dean's mother wondered whether his father might have been a wizard, but nobody has ever discovered the truth: that Dean's father, who had never told his wife what he was because he wanted to protect her, got himself killed by Death Eaters when he refused to join them.

  — JKRowling.com, Extra Stuff: Dean Thomas’s background

Honourable mention

• Mafalda, estranged second cousin of Molly Weasley. Quoting from J.K. Rowling:

  Mafalda was the daughter of the “second cousin who's a stockbroker” mentioned in Philosopher's Stone. This stockbroker had been very rude to Mr. and Mrs. Weasley in the past, but now he and his (Muggle) wife had inconveniently produced a witch, they came back to the Weasleys asking for their help in introducing her to wizarding society before she starts at Hogwarts.

  — JKRowling.com, Extra stuff: Mafalda

  We don’t know whether her father had magical capabilities or not. The fact that they were surprised to produce a witch suggests that he probably didn’t (a Squib, perhaps). Her magical roots still came down the male line, but only barely.

• Hagrid. We know that his father was a wizard, and he had the giantess Fridwulfa as a mother. Although we don’t know much about her magical abilities, we know that giants don’t do much magic. I don’t think Hagrid qualifies as “half-Muggle” though.

In summary

I have drawn up this handy chart which summarises my findings:

However, this only works off a list of named wizards and witches.

What we don’t know (which is just as important) is how many Muggles there are who have one parent who was magical. Only then could we say which parent plays a greater role in determining your magical ability.

It may be that no such individuals exist, as “magic is a dominant and resilient gene”. (JKRowling.com, Extra Stuff: Squibs) I would, however, be quite surprised if that were true.

Answer 2

My answer would be that there is no canon answer for this without extreme digging and extrapolation.

My reasons being:

Nothing can be found on the wikia, Pottermore or from the books or from a interview(to my knowledge) that talks about a certain percentage.

Someone could however name all of the Half-muggles into a grouping and name which parent was a muggle and make a percentage from that. But that is all I know that would work.

My list(if I am wrong feel free to edit or downvote):

Seamus Finnigan-father

Gilderoy Lockhart- father

Minerva McGonagall- father

Malcolm McGonagall- father

Robert McGonagall Jr. — father

Tom Marvolo Riddle/Lord Voldemort — father

Severus Snape — father

Bowman Wright — father

.........................................

Mafalda Hopkins- mother

Dean Thomas — mother

So saying this is all true, then the percentage of muggle fathers is larger than muggle mothers. Also, I consulted the canon where I could, but most of this is taken from the wikia, so reader beware.

2/11 muggle mothers

9/11 muggle fathers

And from that data you could make a percentage from that.

But if this is your answer I fail to see what it proves, sorry not a diss.

My Sources:

Primarily the wikia.

I used the wikia page above to compile this information. And since some of the info I did not know was right or wrong I added another list that I sure of is right and from the book. Some of the information might be from Pottermore that was on the wikia, but I cannot confirm this.

My edited list:

Nymphadora Tonks-father

Seamus Finnigan- father

Tom Marvollo Riddle- father

Severus Snape- father

....................................

Dean Thomas- mother(He states in the Deathly Hallows that his father left when was little so he didn't know if he was a wizard or not. This makes it possible that he could be a muggle-born or Half-muggle)

From this though we can see that the father ratio is still higher than the mother, because there were basically no Muggle woman that had children with wizards.

Unless, you name the woman that was supposedly killed in Deathly Hallows after she said that she did know where someone was(I forget the details). But there is no proof that she was muggle or a squib. But the ratio would still be favoring fathers.

Answer 3

Well, there can be no definitive answer save J.K. Rowling making up an answer. If we assume that the growth of wizarding society follows the same model as real world societies- it is likely that there would be more mothers. As fathers can have any number of children all year long, women on the other hand can only (theoretically) have 2 children per year and therefore more are needed to sustain growth.

A second and more simple metric would be that almost all countries (with the exception of China) have far more females than males so the statistical probability would be in their favor (unless Rowling comes out and says there is a actual likelihood variable between genders).