blue eyes with some brown, is this a single gene (vair) ?

Question

Don't know much about genetics, so forgive the "single gene" reference if I'm totally beside the point.
My son has blue eyes with some beige/brown (not yellow), best seen from the sides, but also visible from the front. It is becoming more visible as he grows. It is not a "spill", or something related to a shock.

I've heard my grandfather's blue eyes were really blue with some brown, and he always claimed it was what we call in French (I'm French, husband Irish BTW) yeux vairs (or just vair. Similar to Vairon, but heterochromy on both eyes). Just wondering, is that an actual "gene" ? It's very hard to get any information on this, only 1 or 2 Wiki articles, in French anyway. Don't know what it is called in English, no luck with heterochromy.

Or is it more likely that my son's mix is just a "combination of genes that went wrong" ? I have dark brown eyes and hair, like both my parents, but my sister is blond haired and blue eyed, so the blue eyes and blond hair did pass down (blond/blue eyed maternal grandma and blond/brown-blue eyed paternal grandad+paternal grandma green eyed) !
My husband is hazel eyed with dark blond hair (exactly same colour as son), his Mum is hazel eyed and father was blue eyed.

I'd love to know more about this ! Thks.

Answer 1

Eye color is polygenic, meaning that it has more than one gene.



The environment is also going to have an effect on the eye color.



And it's also possible that you and your husband carry a recessive gene (both of you must in order for it to be expressed in your kid).

Answer 2

I don't know much about genetics, but I do know that eye color is one of the many traits that is controlled by more than one gene. Certain combination of genes contribute to the color/shade/hue of the iris. So, the mix of genes that your son received from you and your husband all played a part in eye color.



I'm not very sure if that even came close to answering your question, but that's what I know about the subject.

Answer 3

brown is definetly dominant over blue. attempt to think of of it like the brown gene produces brown pigment and the blue gene produces blue pigmet. it relatively is the case in a great form of colour appropriate genetic subject concerns, inclusive of eye colour (there are unusual exceptions). If u combination blue and brown pigment you get brown pigment (like paint). the two the colorations are produced yet whilst they are mixed u can basically see brown. Dominant and recessive is purely an attempt of individuals to describe phenomina purely.