# Population Genetics > Autosomal Genetics >  Phenotype and y-chromosom

## Plutarch

Hello all and excuse me if a similar thread exists!

I have a question and want to give you an example of how I imagine it.

For example, if a man and woman come from different nations who have never crossed their genes, lets say nation a-woman and nation b-man, and they become a male offspring c, fully looking like mother, i.e. a, could then this c have a male offspring e, lets say with a female from a never-crossed-nation d who would fully resemble to him, i.e. to c and a?

Thanks in advance.

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## Sile

So A and B had C who then had E due to a relationship with D .

answer, E would have A B C and D ...........since E is male it would be more similar to B and C ........

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## LeBrok

> Hello all and excuse me if a similar thread exists!
> 
> I have a question and want to give you an example of how I imagine it.
> 
> For example, if a man and woman come from different nations who have never crossed their genes, lets say nation a-woman and nation b-man, and they become a male offspring c, fully looking like mother, i.e. a, could then this c have a male offspring e, lets say with a female from a never-crossed-nation d who would fully resemble to him, i.e. to c and a?
> 
> Thanks in advance.


Are you checking if you're adopted?

You have much bigger chance to look like your father than like your grandfather. Although in 3rd generation sometimes resemblance is still very strong.
On top of it if both parents are from same ethnic group kids look more like parents, than when parents are from completely different nations or continents.

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## Plutarch

I'm actually just asking if the grandson could look equally like the grandmother, and the looks would be transmitted through the y-chromosome only.  :Smile:

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## adamo

I read somewhere that men look twice as much like their mom than their dad. It would then depend on who this guy's mom looks like. Most men I know don't look like their fathers, and good looks are not transmitted paternally. If the mom is rotten then the son will be too. This rule is independent of things like plastic surgery and beautifying techniques of course, as these could explain why some good looking moms/dads have some pretty horrid looking children LOL.

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## adamo

So to answer the question, yes, I think a man can look like his grandma, his maternal one, if that's who his mom looks like more. Either way, men tend to look 200% more like their moms.

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## LeBrok

> I'm actually just asking if the grandson could look equally like the grandmother, and the looks would be transmitted through the y-chromosome only.


I doubt there are any genes on Y chromosome looks related, beside the fact that grandmother can't give her looks in chromosome she doesn't have. If phenotype was located on sex chromosome it would need to be on X for grandma to transmit her "beauty".

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## Plutarch

> I doubt there are any genes on Y chromosome looks related, beside the fact that grandmother can't give her looks in chromosome she doesn't have. If phenotype was located on sex chromosome it would need to be on X for grandma to transmit her "beauty".


Of course they are, because son can look like the father. The question is only if the son can look like the grandmother, this would mean that the x chromosome can fully influence the y.

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## PaschalisB

What are you talking about? Sex chromosomes have nothing to do with the appearance.

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## LeBrok

> Of course they are, because son can look like the father. The question is only if the son can look like the grandmother, this would mean that the x chromosome can fully influence the y.


See the Y chromosome is only a small part of whole human genome. It is around 2%. It directs development of a body into being a man, like testosterone level, muscle tone, sperm production, etc. Y is more like a conductor directing other chromosomes and genes to express themselves correctly into a man. Phenotypical characteristics are overwhelmingly located on autosomal part of DNA, and not on Y, X or mtDNA.
There is no genetic influence of X chromosome on Y chromosome at all. Y chromosome is only transferred from father to son. Y is never transferred to daughters, so tell me how daughters can resemble a father if they don't have Y chromosome, where supposedly looks are stored?

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## LeBrok

> What are you talking about? Sex chromosomes have nothing to do with the appearance.


Generally yes, although one can argue that being a man gives you a different appearance than being a woman. If you have two people with exactly same genes with only Y instead of X in one of them. They will still look extremely similar although one will have more feminine look, the other will be a bit toller looking masculine and will have a penis. Y might not have phenotypical components, but it will influence the look towards masculinity.

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## adamo

I think if the father looks like his mother and the son looks like his father......this man's son COULD look like his grandmother. Although men do in part look like their fathers, they have a tendency of heavily gravitating towards their mothers in appearance.

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## Plutarch

> See the Y chromosome is only a small part of whole human genome. It is around 2%. It directs development of a body into being a man, like testosterone level, muscle tone, sperm production, etc. Y is more like a conductor directing other chromosomes and genes to express themselves correctly into a man. Phenotypical characteristics are overwhelmingly located on autosomal part of DNA, and not on Y, X or mtDNA.
> There is no genetic influence of X chromosome on Y chromosome at all. Y chromosome is only transferred from father to son. Y is never transferred to daughters, so tell me how daughters can resemble a father if they don't have Y chromosome, where supposedly looks are stored?


Of course, the looks are stored in the x-chromosome, because it is the only information that travels from father to mother. 

Are you telling me that there is more information in the sperm than the y-chromosome which gives father's phenotype to the son?

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## Plutarch

> I think if the father looks like his mother and the son looks like his father......this man's son COULD look like his grandmother. Although men do in part look like their fathers, they have a tendency of heavily gravitating towards their mothers in appearance.


If the sperms carry only chromosomes, then they carry also full phenotypes. 

The question is only which one shall prevail, the fathers or the mothers.

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## adamo

The average male is 200% more his mother than his dad. But have multiple kids and you'll see some look more like dad, others like mom; it's pretty random to a certain degree, but I've always believed men are slightly more like their moms.

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## adamo

Like I said, you can have four kids, two look like their mom, one their dad and the other is hard to classify, a mix. Or you can have four kids and they're all more like their mom, it's random. Or you can have a kid that has elements of both parents, that seems possible as well.

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## LeBrok

> Of course, the looks are stored in the x-chromosome, because it is the only information that travels from father to mother.


You are missing some information. Except Y and X chromosomes human genome contains another 22 pairs of chromosomes. These other 22 chromosomes contain great majority of phenotypical information.








> Are you telling me that there is more information in the sperm than the y-chromosome which gives father's phenotype to the son?


 Yes, sperm contains also 22 other chromosomes called autosomal genes (other than sex genes). 
I'm starting to think that you think that only sex genes transfer genetic information during sex.  :Rolleyes:

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## PaschalisB

> Generally yes, although one can argue that being a man gives you a different appearance than being a woman. If you have two people with exactly same genes with only Y instead of X in one of them. They will still look extremely similar although one will have more feminine look, the other will be a bit toller looking masculine and will have a penis. Y might not have phenotypical components, but it will influence the look towards masculinity.


Well, there are XY females too. But that's not what I meant by saying that sex chromosomes have nothing to do with appearance. He was talking about looking like one's father due to the Y chromosome.

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## PaschalisB

> Of course, the looks are stored in the x-chromosome, because it is the only information that travels from father to mother. 
> 
> Are you telling me that there is more information in the sperm than the y-chromosome which gives father's phenotype to the son?


Basic genetics: The sperm has 23 chromosomes. The egg has 23 chromosomes. The fertilized egg has 46 chromosomes. Each human has 46 chromosomes (23 pairs) half from one's father and hald from one's mother. 

It would do no harm to learn some basics before you come to forums like this.

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## Plutarch

> Basic genetics: The sperm has 23 chromosomes. The egg has 23 chromosomes. The fertilized egg has 46 chromosomes. Each human has 46 chromosomes (23 pairs) half from one's father and hald from one's mother. 
> 
> It would do no harm to learn some basics before you come to forums like this.


I thought I had it all, but now, you see what came out.

I was thinking the x-chromosomes are multiplied after the fertilization, and if the gender is male, then only the x of female is multiplied, which would make a probability of 1:45 that the child will look like the father.

But if you say there are also x-chromosomes in the male sperm, then it is hard to say why would the son rather look like the mother.

The study I have read before some 10 years was discussing the phenotype...

Anyway, thank you all for partaking.

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## LeBrok

> Well, there are XY females too. But that's not what I meant by saying that sex chromosomes have nothing to do with appearance. He was talking about looking like one's father due to the Y chromosome.


I knew that you knew, just explained some more, built up on it, for Plutarch.

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## Plutarch

Wait a minute, did someone just said that my y-chromosome could come actually from my mother?

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## LeBrok

> Wait a minute, did someone just said that my y-chromosome could come actually from my mother?


Your mother gave you 23 chromosomes but there was no Y in it. She has two XX. Only men have XY. If father gives X to new child then he creates female, if father gives Y he creates a son.

Only in sporadic situations, bad genes combination, one in 10,000 or so, a person can have too many chromosomes and instead of YX will have YXX. It is called chimera, and person can display both sexes characteristics. I'm not sure though if chimera can have children at all and pass Y to next generation. Anyway Chimera can be classified as both male and female, so this person is not your typical mother to transfer Y.

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## PaschalisB

> Your mother gave you 23 chromosomes but there was no Y in it. She has two XX. Only men have XY. If father gives X to new child then he creates female, if father gives Y he creates a son.
> 
> Only in sporadic situations, bad genes combination, one in 10,000 or so, a person can have too many chromosomes and instead of YX will have YXX. It is called chimera, and person can display both sexes characteristics. I'm not sure though if chimera can have children at all and pass Y to next generation. Anyway Chimera can be classified as both male and female, so this person is not your typical mother to transfer Y.


XXY is called Klinefelter syndrome. The person with this genotype is phenotypically male but can't have children.

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