Neck Length Genetics Inheritance Question

[AmishFighterPilot]

What are the odds that two parents with very short necks could produce a child with a neck that is 3-4 times as long as either parent?

[mrg]

What are the odds that two parents with very short necks could produce a child with a neck that is 3-4 times as long as either parent?

 

That could be determined by obtaining statistics on how often that happens.   I am not familiar with any such study.

[Maine farmer]

I don't want to stick my neck out by attempting to answer this question, but I did find this:  https://www.sciencenews.org/article/giraffe's-long-neck-linked-its-genetic-profile

[AmishFighterPilot]

Thanks. I can only find study data on giraffes, which have surprisingly similar necks to humans except for the size difference. Giraffe studies seem to suggest this cannot happen, but neck variation in humans is probably greater than in giraffes. Even knowing if there aren't obscure variations that may pop up eventually is really hard without any real studies done on the matter.

[Maine farmer]

Thanks. I can only find study data on giraffes, which have surprisingly similar necks to humans except for the size difference. Giraffe studies seem to suggest this cannot happen, but neck variation in humans is probably greater than in giraffes. Even knowing if there aren't obscure variations that may pop up eventually is really hard without any real studies done on the matter.

If you really want to know, you would have to find the answer to a few other questions.  How many genes are involved in determining neck length?  Are these genes dominant or recessive?   What combinations of those genes determine neck length?  Do environmental conditions effect the expression of those genes?   

[AmishFighterPilot]

Excellent points. Its of note in the example I am thinking of that all four supposed grandparents have short necks, just like both parents. It certainly suggests its not a dominant trait if its purely genetic