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  #1  
Old 01-18-2012, 07:48 PM
jjimm jjimm is offline
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Genetically why do all the males in my family look like my great-grandfather?

The earliest photograph of anyone in my family is of my maternal great-grandfather. Facially, he is the absolute spitting image of my grandfather. Now all the males in the maternal line of my family look like him. We're different heights and weights, but the facial resemblance is striking.

Below is an extract from my family tree:
Code:
GGF - GGM
    |
   GF - GM
      |      |  |
      M - F  U1 U2
       |  |
      Me Bro
Those marked in red are people from entirely different genetic stock. Yet those marked in blue all look alike.

When we were younger we didn't resemble each other that much, but now all of us are middle-aged or approaching it, the resemblance to each other and my GF/GGF is absolutely striking.

My biological sister looks nothing like me or my brother - she takes after my dad. Unfortunately for my enquiry, neither of my maternal uncles had sons, only daughters, so I can't see if their progeny look like us too. One of my cousins looks just like my grandmother though.

What's the genetic explanation for such a strong male resemblance despite the repeated injection of genetic material from outside the family?
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  #2  
Old 01-18-2012, 08:02 PM
Colibri Colibri is offline
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There are a wide range of different genes that contribute to facial appearance. In your family's case, the group of alleles of different genes that produced your great-great-grandfather's facial appearance just happened to have been passed on together, more so than is average among families. It's coincidence, nothing more.
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Old 01-18-2012, 08:09 PM
Shagnasty Shagnasty is offline
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Are you sure the resemblance is real than just a restatement of what other family member have repeated lots of times? I am not doubting you but photos would be helpful. People tend to pick upon different facial cues in very different ways even within the same person and other people see it very differently.

It could also be chance as well. My father's side of the family mostly dominates the appearance of me and my two brothers. I have two daughters and the oldest one is clearly not only mine but also also a member of my father's side of the family going back many generations. You could dress her in period clothes and put her in any paternal family photo going back since cameras existed and she would fit right in. The younger one is more of a gradual blend I always assumed those things happened in most families although I would love a good explanation for dominance of one line as well.

Last edited by Shagnasty; 01-18-2012 at 08:10 PM..
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  #4  
Old 01-18-2012, 08:19 PM
SciFiSam SciFiSam is offline
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Chance and observation bias.

It does sometimes seem as if some features apart from the usual eye colour ones can be 'dominant;' all my Dad's many kids, from different mothers, and all of their many kids (with one exception, possibly because she's mixed-race, though her sister is no exception), and now their kids' kids, look strikingly alike. We all look like my Dad's Dad. I could pick up my great-niece - the child of the child of my half-sister - and she'd look like my daughter. It's as if the features of the other parents get filtered out.

My daughter is the one exception in hair colour - the sole blonde out of about 30 grandkids - but facially she looks just like my paternal Grandad, as we all do. It's even a bit odd that my Dad is a carbon copy of his Dad, since his Mum was African/Indian and his Dad a white Brit. Even the more 'African' features in my family are ones my Grandad also had, because things like dark curly hair are not uniquely African.

'That man had some strong genes' is the thought that goes through my head, but it still has to be most likely down to chance and observation bias.
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Old 01-18-2012, 08:23 PM
jjimm jjimm is offline
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Re. observation bias: perhaps, but I always thought that I was the exception to the facial resemblance thing - it was when I unexpectedly saw a picture of myself in black and white, and thought it was of my granddad, that I realised I have got 'the look' too. I don't have access to pics of the others unfortunately, but if we were all part of a line-up you'd think we were brothers.
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  #6  
Old 01-18-2012, 08:30 PM
John DiFool John DiFool is offline
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A friend of my dad's had 3 girls-2 of which looked like him (light brown hair, round face), one of which looked like his wife (dark brunette, thin face).
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  #7  
Old 01-18-2012, 08:47 PM
dropzone dropzone is offline
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Dominance. Submission. Radios appear.

Ads, but they won't kill you. And, for a change, the boys go as many as five words before they get incoherent. But try to think of yourself as dominant, though your SO might laugh at the suggestion.
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  #8  
Old 01-18-2012, 08:56 PM
dropzone dropzone is offline
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FTR: Oldest got my nose. Bad for her, but at least the other two did not get the One-D-Adams nose, which is why I selected their mother over some of her sisters.
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  #9  
Old 01-18-2012, 11:28 PM
jjimm jjimm is offline
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Quote:
Originally Posted by dropzone View Post
You know that's from one of my favourite albums ever?
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