You are another culturally programmed millenial internet dude with this weird bitterness towards women. One female accuses a guy of mansplaining incorrectly and you come here to “delight” in her downfall. The culture is sick and it makes me sad.
Penny Davis to those talking shit about mountain people, go say all that shit to their face, see what happens....Appalachians are the REAL builders of this nation between mining everything from copper, coal, iron ore, ETCETERA....There wouldn’t be a decent bridge, ship, sky scraper, or plane without the Scot Irish immigrants busting their asses for little to nothing, they came as indentured servants, bought that mountain land because no one wanted it, and never asked no one for shit, as they became the volunteer state in Tenn. because they kicked ass and still can, so by all means go call them inbred and see what happens!....Mentally disabilities happen often with zero inbreeding involved...Get your lazy asses in those mines and obtain some heavy metal poisoning, then talk about shit!
They are not FDA approved so they have no one ensuring accuracy nor reviewing their processes. They say they're using top of the line tech, but are they? Note the price point cause you get what you pay for.
I'm not an expert or anything I just know I looked into 23 and me cause I had a close relation die of a deadly cancer. The general agreement was that this was a fun toe dip into the waters of genetics but in no way should be construed as actionable medical information, and any good doctor would require you to get medical genetic testing to confirm anything the report said anyway so you might as well start with them.
For many diseases, the link to genetics is known, but all it does is affect your risk of getting the disease. Just because you have the risk allele(s), doesn't mean you are doomed.
Many doctors cling to these tests simply because they are FDA approved and want to cover their asses. For a while, medical companies were able to patent the genetic testing of certain causal genes and so 23andme would not have been able to include those genes in their kit. This was struck down in 2013.
Inbreeding is much more easy to detect. Inbreeding leads to you having two copies of the same allele (homozygosity). This can cause problems because you are more likely to be homozygous for an autosomal recessive disease, a disease where you need two bad copies. Inbreeding is easy to detect because you just need to look for large swaths of your genome which are homozygous. If this happens more than you would expect by chance, inbreeding.
The PDHS indicated that more than half of ever married women aged 15-49 were married to their first cousins. The inclusion of second cousins raised the percentage of consanguineous marriages from 50.3 to 61.2.
For anyone wondering, for entirely unrelated parents and ignoring crossing over, the whole thing is basically flipping 46 fair coins and counting how many came up heads (because for each chromosome there's 0.5 probability that you got it from the same parent).
This is called binomial distribution, we are interested in the chance of flipping 46 * 0.77 = 35.42 or more heads and quick check with scipy says that 1 / binom.sf([34, 35], 46, 0.5) is between one in 3734 and one in 12786 (we need to subtract one because it's survivor function that says how much probability remains strictly above the given number, while we need inclusive). Also, that's only one tail, there's the symmetrical chance of someone getting 23% or less matching chromosomes with their sibling.
So all the mouthbreathers saying "mathematically impossible" in that thread are a bit inbred themselves, but yeah, pretty suspicious.
Other fun binomial facts: you have a ~50% probability of having 23 +- 2 matching chromosomes and 99% probability of having 23 +- 9 (or 30% - 70%), and as you can see the chances keep dropping exponentially outside that.
I was surprised to see how much bad probability/statistics was going on in that thread.
Given that those 46 coin flips happened 7 billion times already it really isn't surprising at all that this particular distribution appears. Hell, 1 in 12786 alone is like one person in a small city.
You are wrong, and the people saying it's "mathematically impossible" are much closer to being right. Because your analysis is based on a faulty premise.
People think we inherit 23 whole chromosomes from each of our parents, and that's true. Some people also think, as you assume here, that those 23 whole chromosomes are the same full chromosomes that each parent inherited from their parents (ones grandparents). That's false.
Generation of gametes (eggs, sperm) involves meiosis, which involves genetic recombination, meaning that each chromosome from each parent is a random mixture of grandparents DNA. Recombination happens in chunks, the sizes of which vary, but they are ballpark 100 kilobases. The human genome is about 3 gigabases
Meaning there are roughly 3e9 / 100e3 = 3e4 coin flips happening here. Go ahead and re-run the stats and see what the chances of 77% of 30,000 coinflips being heads. Here's what I got:
1 / scipy.stats.binom.sf([20000, 25000], 30000, 0.5)
<string>:1: RuntimeWarning: divide by zero encountered in true_divide
array([inf, inf])
The probability is so small it causes a floating point underflow. Next time you wanna shoot off about statistical genetics, make sure you understand basic genetics.
With a 99% range. What I don't understand is why the average is around 2/3rds of the full range of 3400:
Half-identical on 50%/1700 cM and fully identical on a further 25%/850 cM.
Can you explain?
Anyway, for purely eyeballing purposes I just multiplied the total by 1.5, printed that range, then calculated the virtual n that would give a similar range, looks like it's is indeed slightly above 2 * 46 (but kinda different and I feel that this half-identical/fully-identical stuff really messes things up).
Okay, seriousposting time I guess. I work in genetics but not reproductive genetics so this is a little outside my area of expertise. OP of the thread is most likely inbred (either directly from their parents or their community has higher-than-normal average relationship). Genetics can be weird and maybe some other weird thing happened, like a sample failure and/or copy number event, but it's not just noise.
Which (assuming the same rate for eggs) gives much scarier numbers, sure: [ 3739615.66853563 12370020.67672898],
This is 3.7 billion to 12.3 billion. Earths population is 7.5 billion. It's also probably higher (ie less likely) than this because you assumed the same for egg as for sperm, but apparently there are more crossings in eggs (~48 recombination events compared to 23, if I'm interpreting the centimorgans measurement correctly).
40 comments
1 SnapshillBot 2018-07-26
You are another culturally programmed millenial internet dude with this weird bitterness towards women. One female accuses a guy of mansplaining incorrectly and you come here to “delight” in her downfall. The culture is sick and it makes me sad.
Snapshots:
I am a bot. (Info / Contact)
1 Scarytownterminator 2018-07-26
You don’t know me.
1 [deleted] 2018-07-26
[removed]
1 respaaaaaj 2018-07-26
oooofff two people found out they were the product of inbreeding in that thread.
1 pitterpatterwater 2018-07-26
If it makes them feel better, I'm somewhat ingress and have no major health problems.
1 IqtaKadabra 2018-07-26
Is that why you chose to work in tech?
1 pitterpatterwater 2018-07-26
Nah, but it's why I'm a GUI RAID programmer.
1 Power_Incarnate 2018-07-26
We all know you're Paki, no need to keep reminding us.
1 reallyrunningnow 2018-07-26
REEEEE
1 constantinople_2053 2018-07-26
just getting it out of the way early
1 helppls555 2018-07-26
woke
1 MG87 2018-07-26
Go Hookies?
1 OniTan 2018-07-26
Can't spell funnel without fun.
1 cleverseneca 2018-07-26
People acting like 23andme is accurate to the level needed to identify these things.
1 TheRobidog 2018-07-26
^ Product of incest
1 cleverseneca 2018-07-26
I wish, then I'd have an excuse for being a /r/drama poster!
1 ItsSilverFoxYouIdiot 2018-07-26
... it is. Am I missing something? They use the same technology as GWA studies. They use the same IBD/IBS tools.
1 cleverseneca 2018-07-26
They are not FDA approved so they have no one ensuring accuracy nor reviewing their processes. They say they're using top of the line tech, but are they? Note the price point cause you get what you pay for.
1 ItsSilverFoxYouIdiot 2018-07-26
The chips used in GWA studies aren't FDA approved either.
1 cleverseneca 2018-07-26
I'm not an expert or anything I just know I looked into 23 and me cause I had a close relation die of a deadly cancer. The general agreement was that this was a fun toe dip into the waters of genetics but in no way should be construed as actionable medical information, and any good doctor would require you to get medical genetic testing to confirm anything the report said anyway so you might as well start with them.
1 ItsSilverFoxYouIdiot 2018-07-26
I am an expert.
For many diseases, the link to genetics is known, but all it does is affect your risk of getting the disease. Just because you have the risk allele(s), doesn't mean you are doomed.
Many doctors cling to these tests simply because they are FDA approved and want to cover their asses. For a while, medical companies were able to patent the genetic testing of certain causal genes and so 23andme would not have been able to include those genes in their kit. This was struck down in 2013.
Inbreeding is much more easy to detect. Inbreeding leads to you having two copies of the same allele (homozygosity). This can cause problems because you are more likely to be homozygous for an autosomal recessive disease, a disease where you need two bad copies. Inbreeding is easy to detect because you just need to look for large swaths of your genome which are homozygous. If this happens more than you would expect by chance, inbreeding.
1 cleverseneca 2018-07-26
You missed my last most important point: is your username a Malazan reference?
1 ItsSilverFoxYouIdiot 2018-07-26
No, it's from a time a chick tried to hit on me. She called me a "grey fox" and I told her it was "silver fox" and called her an idiot.
1 Automaticus 2018-07-26
UNLESS YOURE PAKISTANI.
PLS DONT B RCIST
1 pitterpatterwater 2018-07-26
Agendapost somewhere else pls.
1 Automaticus 2018-07-26
Sorry what agenda is that?
The PDHS indicated that more than half of ever married women aged 15-49 were married to their first cousins. The inclusion of second cousins raised the percentage of consanguineous marriages from 50.3 to 61.2.
https://www.ncbi.nlm.nih.gov/m/pubmed/12346199/
1 pitterpatterwater 2018-07-26
You're boring, keep your autism is relevant threads.
1 Automaticus 2018-07-26
Sjwz in my drama?
1 zergling_Lester 2018-07-26
For anyone wondering, for entirely unrelated parents and ignoring crossing over, the whole thing is basically flipping 46 fair coins and counting how many came up heads (because for each chromosome there's 0.5 probability that you got it from the same parent).
This is called binomial distribution, we are interested in the chance of flipping 46 * 0.77 = 35.42 or more heads and quick check with scipy says that
1 / binom.sf([34, 35], 46, 0.5)is between one in 3734 and one in 12786 (we need to subtract one because it's survivor function that says how much probability remains strictly above the given number, while we need inclusive). Also, that's only one tail, there's the symmetrical chance of someone getting 23% or less matching chromosomes with their sibling.So all the mouthbreathers saying "mathematically impossible" in that thread are a bit inbred themselves, but yeah, pretty suspicious.
Other fun binomial facts: you have a ~50% probability of having 23 +- 2 matching chromosomes and 99% probability of having 23 +- 9 (or 30% - 70%), and as you can see the chances keep dropping exponentially outside that.
1 Peetrius 2018-07-26
I was surprised to see how much bad probability/statistics was going on in that thread.
Given that those 46 coin flips happened 7 billion times already it really isn't surprising at all that this particular distribution appears. Hell, 1 in 12786 alone is like one person in a small city.
1 zergling_Lester 2018-07-26
Yeah.
Though I doubt that 32andme has tested 7 billion pairs of siblings, you gotta account for that.
1 respaaaaaj 2018-07-26
Its bad stats but good genetics lol, its not 46 coin flips
1 Peetrius 2018-07-26
Listen buddy, as someone who has extensive knowledge from browsing 23andMe I'm an expert in the field.
1 respaaaaaj 2018-07-26
Listen buddy, as someone who has extensive knowledge from scraping a B- in high school human biology I'm also a expert in the field.
1 Rivea_ 2018-07-26
I came here to say this and also point out that the people who originally took part in that thread did the following things simultanoeusly:
How can you reconcile these things and not realise something is wrong?
1 youcanteatbullets 2018-07-26
You are wrong, and the people saying it's "mathematically impossible" are much closer to being right. Because your analysis is based on a faulty premise.
People think we inherit 23 whole chromosomes from each of our parents, and that's true. Some people also think, as you assume here, that those 23 whole chromosomes are the same full chromosomes that each parent inherited from their parents (ones grandparents). That's false.
Generation of gametes (eggs, sperm) involves meiosis, which involves genetic recombination, meaning that each chromosome from each parent is a random mixture of grandparents DNA. Recombination happens in chunks, the sizes of which vary, but they are ballpark 100 kilobases. The human genome is about 3 gigabases
Meaning there are roughly 3e9 / 100e3 = 3e4 coin flips happening here. Go ahead and re-run the stats and see what the chances of 77% of 30,000 coinflips being heads. Here's what I got:
The probability is so small it causes a floating point underflow. Next time you wanna shoot off about statistical genetics, make sure you understand basic genetics.
1 zergling_Lester 2018-07-26
I said that I'm ignoring crossing over, that probably was a mistake.
However, your numbers are way off:
Which (assuming the same rate for eggs) gives much scarier numbers, sure: [ 3739615.66853563 12370020.67672898], but still not anywhere near infinity.
Also, https://en.wikipedia.org/wiki/Centimorgan says:
Which should translate to 47 + 28 crossing-over events? Or that divided by two?
Then we can do much better and go straight to one of the sources: https://isogg.org/wiki/Autosomal_DNA_statistics#Distribution_of_genealogical_relationships_for_given_amounts_of_shared_DNA
Now, for siblings they give
low, avg, high = 2209, 2629, 3384
With a 99% range. What I don't understand is why the average is around 2/3rds of the full range of 3400:
Can you explain?
Anyway, for purely eyeballing purposes I just multiplied the total by 1.5, printed that range, then calculated the virtual n that would give a similar range, looks like it's is indeed slightly above 2 * 46 (but kinda different and I feel that this half-identical/fully-identical stuff really messes things up).
https://ideone.com/MwW7OL
1 youcanteatbullets 2018-07-26
Okay, seriousposting time I guess. I work in genetics but not reproductive genetics so this is a little outside my area of expertise. OP of the thread is most likely inbred (either directly from their parents or their community has higher-than-normal average relationship). Genetics can be weird and maybe some other weird thing happened, like a sample failure and/or copy number event, but it's not just noise.
This is 3.7 billion to 12.3 billion. Earths population is 7.5 billion. It's also probably higher (ie less likely) than this because you assumed the same for egg as for sperm, but apparently there are more crossings in eggs (~48 recombination events compared to 23, if I'm interpreting the centimorgans measurement correctly).
1 zergling_Lester 2018-07-26
Million.
1 youcanteatbullets 2018-07-26
Gah, apparently I can't read. Still, 3-12 million is long odds.
1 zergling_Lester 2018-07-26
At least you can teat bullets!
1 Jimbo_B_Beterson 2018-07-26
I thought it was supposed to be a family pole