Question for Atomic about a research article

[Jjarrel1]

Hello!

I was on this site briefly about 2 years ago now when we were TTC our second baby. I ended up having an ectopic pregnancy and losing a tube. Then I freaked out and we just did the sperm meets egg plan and ended up conceiving our DS2 just 2 months after my surgery!

I am now pregnant again (just found out last week!) after doing a pretty light girl sway (LE diet but not nearly as restrictive with calories as I was when TTC DS2. And we ended up with 2 attempts in my fertile window).

Anyway, my family hasn't had a baby girl on either side for 17 years. My husband's family hasn't had a girl since his mom was born about 60 years ago. DH has 4 brothers and his mom got pregnant with a fifth boy but miscarried him. No girls! His mom does have an older sister but they are the only 2 girls on his mom's side of the family. His dad's family has only had boys for generations.

I came across this article and was wondering your thoughts on it--Atomic and anyone else! It's an interesting theory but doesn't the process for producing sperm cause 50 percent female and 50 percent male sperm to be produced? So are they suggesting that, in our family for example, there are less female sperm because they just...die or something? It just doesn't make sense to me!

Here is the article!

https://www.sciencedaily.com/release...1211121835.htm

[Throwaway_panther]

Hello!

I was on this site briefly about 2 years ago now when we were TTC our second baby. I ended up having an ectopic pregnancy and losing a tube. Then I freaked out and we just did the sperm meets egg plan and ended up conceiving our DS2 just 2 months after my surgery!

I am now pregnant again (just found out last week!) after doing a pretty light girl sway (LE diet but not nearly as restrictive with calories as I was when TTC DS2. And we ended up with 2 attempts in my fertile window).

Anyway, my family hasn't had a baby girl on either side for 17 years. My husband's family hasn't had a girl since his mom was born about 60 years ago. DH has 4 brothers and his mom got pregnant with a fifth boy but miscarried him. No girls! His mom does have an older sister but they are the only 2 girls on his mom's side of the family. His dad's family has only had boys for generations.

I came across this article and was wondering your thoughts on it--Atomic and anyone else! It's an interesting theory but doesn't the process for producing sperm cause 50 percent female and 50 percent male sperm to be produced? So are they suggesting that, in our family for example, there are less female sperm because they just...die or something? It just doesn't make sense to me!

Here is the article!

https://www.sciencedaily.com/release...1211121835.htm

No, that's not what it's suggesting. It's positing that there may be a yet unidentified allele combination associated with sperm that results in frequency of girls/boys. It's not that girl sperm just die -- it's that for some men, they have something specifically that edges out the Y sperm. Others have an edge for X, and still others have no edge to either.

To put it in maybe easier to understand terms, it's saying that having boys or girls is almost dominant or recessive depending on family.

So think of it as a punnet square, and I'll use the example of red heads since I just read something on it. If a mom and dad both have red hair, they carry that gene and are likely to pass it onto their kids. Now say they have blonde and brunette siblings, they carry these genes as well. So one of their kids ends up brunette.

Now say this brunette child has kids with a red head. Again, possible to have red head kids. Say this brunette has kids with a blonde with a family of redheads -- STILL possible for red heads, but not as likely. Even more interestingly, a recent study found this about red beards: say this brunette marries a blonde with no history of red heads and has a blonde or brunette son; that son could end up with a red beard!

So this study is suggesting it's something like this. In this case, knowing what we know about sperm and just evolution in general, EVERYONE has a shot at a boy or girl, but some people might have more shots than others.

Another example is eye color -- my DH and I had a 50% shot for brown eyed kids, 37.5% for green, and 12.5% for blue. Our DD has solidly blue eyes.

So even if odds seem bad, there is always a chance for those slim margins.

This is an old study, but this arguably supports what I've seen atomic suggest, that some of us might just be set more for a particular gender. This suggests it's more male oriented, which I personally think IS something to not discount, but outside of killing sons in wars every generation, there's only so much to impact that. Swaying is where we try to bump the odds knowing the science behind those tactics with other things.

Because, afterall, even these boy or girl heavy families get girls or boys. My DH is one of 3 boys, 1 girl -- we got a girl because of all of my unintentional girl swaying! With blue eyes, which we had an essentially 10% chance of haha

[Jjarrel1]

Ah I see! So equal amounts of male and female sperm are produced but (in the case of our family), the male sperm have some sort of unidentified "edge" over the female sperm? So they are basically more likely to fertilize the egg and/or create a successful pregnancy.

I was thinking this article does support what Atomic has always believed to be true. The authors acknowledge that men's probability of having male or female children can be predicted to some extent, but women's probability really can't be predicted at this point. When I read that, I was thinking that this is where swaying comes into play! Women are unpredictable to some extent because as we change lifestyle factors like diet, exercise, frequency of sex, emotional health etc, we unintentionally or intentionally sway boy or girl.

Thanks for your response!

[atomic sagebrush]

It's not genetics (or very, very unlikely to be and not in the straightforward way you are thinking about it.) I have talked to several geneticists and evolutionary biologists about this and they all thought the study was junk and that the media coverage was a joke since they all reported this in a very misleading way as having been discovered when it hadn't been and almost certainly never will be.

The author of the study (who was a grad student BTW, this was some sort of project they were doing for school using old census records and stuff like that, NOT a new study done using modern birth records) noticed that gender does seem to run in the family with some families having more boys than girls and vice versa. But then they jumped to the HUGE, totally unproven conclusion that this was some sort of gene thing when it literally CANNOT be. Here is why: If there was such a gene, particularly for boys to be conceived, carried on the Y chromosome and directly genetically inheritable from father to son, because historically XY are much less likely to survive to adulthood to pass down genes, this gene would be at a major disadvantage.

How major? Well, of all the men who have ever lived, only 40% have surviving descendants today, while 80% of all women who ever lived do. Additionally, we know for a fact based on DNA evidence that as little as 4000-8000 years ago, 17 women reproduced for every one man. A gene that hitched its cart to that train wreck would NEVER have survived to be handed down to future generations. It would have been eradicated from the genome entirely. Genes that are passed down favor survival of themselves, not a 16 in 17 chance of dying out forever. Any gene that was that suicidal, to hook itself to the male sex would no longer exist now to be handed down to my son and your son, and even if it DID, how could it have recovered in that time...meaning if only 4000 years ago, 16 out of 17 people or even just a fraction of them, had some "all girl" gene, how could we have 50-50 gender ratio all around the world everywhere today in all of written history?? Wouldn't we still have more females born than males (instead of the other way around)? And how can it be explained, if this is some gene, that all races and ethnicities worldwide, no matter how genetically isolated, have about 50-50 boys and girls?? If the gene were in some population somewhere, we would have seen some tribe or nation that had skewed gender ratios but we don't and never have in all of recorded history.

The math behind why the gender ratio stabilizes at 50-50 and cannot be genetic was demonstrated back in the 30's and it is still accepted today (and I can explain more about this if anyone is interested in that) Called "Fisher's Principle" after its discoverer, Robert Fisher, and that dude hung out WITH Punnett himself and was expert in the squares.

What makes the most sense is for genes to favor the survival of the gender that has the best chance of surviving to adulthood to pass down genes and in most animals, that can vary depending on the environment, and most animals have the capability of altering that gender ratio based on cues from the environment. Now, in humans, some things tend to run in the family (and this is the part that may be partly, slightly, to a miniscule and minor degree, genetic). Food preferences. Height. Athleticism. Even mate selection may be to some extent programmed. There are dozens if not hundreds of things that could run in a family, not even genetically but simply because you do things like your parents do them (especially where food is concerned) or because you and your sister ate the same food from birth to age 18 or because a guy married a girl like mom or whatever. This doesn't therefore prove that this is a dominant and recessive gene controlling gender and in fact every other scrap of biological evidence points to the direction that it is not, and cannot be set up that way.

Yes, men are made of XY cells that divide in the testicles to make half x and half Y sperm. Additionally, men have had their sperm tested and always had about 50-50 (and any study that says otherwise used an outdated method of counting X and Y sperm or was done by charlatans selling gender swaying methods) so no, they don't die off either. There may be something going on with sperm communication or dormancy or whatever but we would not be seeing the kind of results we are with maternal diet and gender swaying if there were men who could only make X or Y sperm. IT doesn't add up.

I often have people show up on here with a story about 3 generations or 17 years or whatever but that's the way that randomness works. If every family always had precisely 1/2 boys and 1/2 girls, then that really would be weird!! In a random system, there will be runs of all one or all the other but they will even out over time.

In my family, we went for 20 years and had 8 boys and one girl. Then within a few years, I had a daughter, my sister had a daughter, 2 of my cousins had 2 daughters apiece and another cousins had one girl! My brother also had a boy during that time. This ends up being 9 boys and 8 girls, much more 50-50 breakdown. But if you'd looked at either end of that, you'd think our family was genetically set for boys or girls, but it wasn't true. It's just a trick of statistics over time that makes it look that way.

[atomic sagebrush]

Panther my husband and I both have brown eyes and have TWO blue eyed kids. So annoying because total strangers will insist "that's impossible" and peer at me like I have been up to no good.

[Throwaway_panther]

I laughed out loud! These people need the punnet square thrown at them!

[Jjarrel1]

Thanks Atomic for your insight on this!! I knew you would have the inside scoop. The conclusions drawn from this article did just seem really fishy to me, which is why I wanted to ask you. What you said about it making no sense for this gene to exist from an evolutionary standpoint is something I thought about too. Your explanation makes a lot of sense.

We have had a very long boy streak on my side of the family and a ridiculously long one on my husband's side! I don't know if you have ever watched the Duggar family on TV...I don't usually watch but I do find it so interesting that she had a streak of like 6-7 boys or something in a row! Which would make you think her family could "only" have boys if those were the only kids she had. But the 19 that she ended up having are split pretty evenly between boys and girls.

Someone has to break this boy streak in our families! It could be us...We shall see!

[atomic sagebrush]

Yes I use the Duggars as an example all the time. They start off having BG mixed, then a run of boys, then a run of girls, and all three of them were longer than most families. These are the exact same people genetically, and yet they had these three long runs of gender makeups - and in some families, even just their long runs of boys, well, that's the same # of children produced by whole entire 2-3 sibling families. And then overall where does it settle? About 50-50. There's a weird kind of magic to it.

Yes that's how you should think of it, it's not that this means you cannot have a girl, it actually ~may~ mean that someone is gonna have a girl and it may as well be you!!! If you were tossing a coin for 17 years and getting nothing but heads, it wouldn't be a dumb bet to bet tails even if the coin was a little bit weighted towards heads.

[The Anchor]

I laughed out loud! These people need the punnet square thrown at them!