What are the chances of this.....My brother is brown eyed and so is his wife....His first child has the brightest blue eyes,...at first there was some raise of the eyebrow, but hey it could happen, right?......Well, guess what?...the second child has BLUE eyes too...what luck...does anyone else know of a situation like this?.... Here's a special note....she was married before to a blue eyed man which produced 3 children...2 of which have BROWN eyes and the other blue...would love to hear your input on this....also, you should know we all love our new sister-inlaw...
2008-05-25T10:40:24Z
Blue eyed would be chance..... 2 for 2???
Deathbunny2008-05-24T22:46:03Z
Favorite Answer
Blue eyed genes are recessive, only two blue genes together will produce blue eyes. If just one brown gene shows up, then the eyes are brown. So:
blue + blue = blue blue + brown = brown brown + brown = brown
Both parents have a 50-50 chance of either gene showing up in a child (generally).
Okay, your brother's wife carries both a brown-eyed gene and a blue eyed gene. Her ex had blue eyes--both genes blue. This showed up in her kids with him, each should have a 50% chance of blue (blue from dad and blue from mom) or brown (blue from dad and brown from mom).
So, your brother has brown eyes.
He can either have a brown + brown or a blue + brown.
If he's brown + brown, then all of his children would recieve at least one brown gene and all should be brown eyed.
If he's brown + blue, then there is a 25% any child he had with his wife is going to be blue eyed. Why?
Brother's gene + Wife's gene = Kid's color blue + blue = blue blue + brown = brown brown + blue = brown brown + brown = brown
So, I would look at your parents--are either blue eyed?--and your grandparents--any blue eyes?. With a recessive trait like blue eye color and a 50% chance of passing it and having it hidden, it's easily possible for the genes to skip several generations.
Now, if your brother and his wife have three more kids and most are blue eyed... Then you have to wonder.
(And I explained it without the words genotype, phenotype, allele, and linkage. Go me!)
EDIT: Daddy in a box: red and blond hair are still adaptive in northern latitudes due to UV light. If you don't think so, try an experiment: have you and your wife (and kids) stop drinking cow's milk, switch to a vegan diet, and live in North America or Europe...
Dark skin in Europe only lasts as long as the dietary supplements (Vitamins, Vitamin D enriched milk, fish oil, maybe liver) and tanning booths last.
My ex and I both have brown eyes. In fact he was Mexican. Our daughter has blue eyes. The answerer above is ENTIRELY incorrect...what he gave is an 8th grade text book, simple, dumbed down explanation. However in reality genetics are much deeper than that, and in fact include any traits that are possessed by ANYONE in that family for several generations back. For me my mom had blue eyes and his dad (from Spain) had blue eyes, and with an understanding of genetics, one would understand how we brown eyed people ended up with a blue eyed daughter I have twins with my husband.....the girl got his blue eyes and my dark hair and the boy got my dark eyes and his light hair.
1. Do either of your parents or grandparents have blue eyes? 2. Do either of her parents or grandparents have blue eyes?
Blue is a recessive gene. A brown eyed person can carry this gene.... and if two brown eyed people have this recessive gene and both pass it on, then yes, they can have a blue eyed child.
If you had said they both had blue eyes and had a brown eyed child I would wonder... because it takes recessive genes from both parents to have a blue eyed child... so for two blue eyed people to have a brown eyed child would be extremely rare.... but two brown eyed to have a blue eyed child.. very possible!
Sadly, Daddy in a Box got this one wrong. Sadly for him that is.
I have green eyes and both of my parents have brown eyes. I got my eye color from my aunt and grandmother on my dad's side who both have green eyes. My brother has hazel-brown eyes.
On a rare note, my husband has blue eyes and I have green eyes. Strangely, our son has hazel-brown eyes. Must've gotten that gene from my side of the family as they are the same color as my brother's.
Genetics go way beyond the Mendellian box most of us learned in high school and college. There usually isn't just one gene from each parent that determines eye color, hair color, skin color or anything else. It's a conglomeration of everything we've been passed down through all of our ancestors.
So, yes, it's definitely possible for your brother and sister-in-law to have 2 children with blue eyes.
Are there any blue eyes further back in the family tree?? I know that I had blue eyes until I was about 18 months & they don't run in my family. Also, there's red hair about 4 generations back in my family; everyone else has brown; yet I have several cousins with carrot top hair.