Can two blue eyed people have a brown eyed child?Sitema40 - 6 Answers
Eye color in humans is not simply controlled by one set of genes. There are three different genes that are known so far to affect a person's eye color, the bey 1 gene, the bey 2 gene, and the gey gene. Each of these genes has 2 different forms or alleles and you inherit one allele from each parent so that your two alleles on each gene are a mixture of what your parents had.
The bey 1 gene has two alleles that are considered the central brown genes. The bey 2 gene has a brown and a blue allele, and the gey gene has a blue and a green allele. All brown alleles are dominant over blue or green alleles which means if you have only one brown allele then you will have brown eyes. The green allele is dominant over blue alleles so if you have no brown alleles and one green allele then you will have green eyes. Finally the blue allele is recessive to all other color alleles which means to have blue eyes you must have all blue alleles.
This means that for the parents to have blue eyes they must have only blue alleles and having only blue alleles means they can only pass on blue alleles to their children. Their children will only have blue eyes under normal conditions but there can always be genetic mutations but those would be very rare.
As Facers22 has elaborated brown alleles are dominant,blue are recessive and all the others are in between.
I have however observed that your bloodline is almost as important as genetic dominance or recession.
Blue eye-coloured parents will easily get brown eyed children if their family line is dominated by brown eyed people.Despite blue colour being recessive,the opposite happens where blue eyes dominate(In Estonia and part of Western Russia where 95%+of the inhabitants have blue eyes,two brown eyed parents will most likely have blue eyed children despite brown being dominant due to blue dominating their bloodline hence is dominant in their genetic structure).
Among Caucasians,Americans,due to the mixing of people from every region of Europe are the most unpredictable when it comes to eye colour.Here,brown eyed parents can get blue,green and honey eye-coloured infants though it is not that common,it happens.So,yes two blue eyed parents can get a brown eyed child.Especially in the USA.
Since blue eyes are a recessive trait, the parents do not carry the dominant allele for brown eyes. Therefore there is no chance, unless a mutation occurs, for their children to have blue eyes.
On the other hand, two brown eyed parents can have a blue-eyed child. I am living proof of this. The reason is that brown is dominant. So if both parents who have brown eyes carry a recessive allele for blue eyes, their children have a one in 4 chance of inheriting the two recessive alleles and therefore having blue eyes.
I think it is possible for two blue eyed people to have a brown eyed child if a blue eyed person has direct blood relatives who have brown eyes, although it's unlikely. My mother has brown eyes, my father has very light blue eyes, and one of my sisters and i have dads blue eyes, while my other sister has green eyes. My mums mother is the only directly related relative who also has green eyes, so my little sister must have gotten the green eyes from genes my mother has from her mother....
Its possible, blue eyes must be dominate and brown could be recessive. Its all based on luck....
Yes, it is possible, but it is not as likely as it would be if two brown eyed people did....