My mom and dad both have brown eyes, one of my brothers has brown eyes, and me and my other brother have green eyes. How did this happen? No one else even in our extended family has green eyes.
We are not adopted and I know my dad is my real dad.
2007-11-10 08:55:30 · 4 answers · asked by DeAnna 5 in Health ➔ Optical
Eye colour is not inherited via just one gene.
DNA Canada has proposed an eye colour inheritance model that assumes there are six genes involved and each can either be for light or for dark eyes, with dark dominating light. In the model they propose seven eye colours varying from very light blue with 6 light genes and 0 dark genes to dark brown with 0 light genes and 6 dark genes. Hazel is the mid point with 3 genes of each type. The others are:
blue (5 L, 1D), green (4L, 2D), light brown (2L, 4D) and brown (1L, 5D).
You and your siblings inherited 3 genes from each parent. From mom, if eyes are light brown, child will inherit one of these combos:
(2L, 1D), (1L, 2D), (0L,3D)
And from dad, if eyes are light brown, child will inherit one of these combos:
(2L, 1D), (1L, 2D), (0L,3D)
Adding the genes together, children could have any of the following combinations:
0L, 6D -- dark brown
1L, 5D -- brown
2L, 4D -- light brown
3L, 3D -- hazel
4L, 2D -- green
2007-11-11 06:33:32 · answer #1 · answered by Judy B 7 · 0⤊ 0⤋
well it is all genetics. Brown eyes is a dominant trait. meaning if u have 1 dominant brown eye trait you will have brown eyes. U need 2 green eyed traits to be green eyed.
Both your parents have 1 green eye trait in them it doesnt show. They passed it down to only 1 brother
your brother has 2 green eyed traits.
learn genetics
2007-11-10 09:02:45 · answer #2 · answered by dah man wit no plan 1 · 0⤊ 1⤋
its to do with dominant and recessive eye colour in your parents genes, like you my and my brother have blue eyes but my parents have both got brown eyes.
If your mum has brown eyes she might have the brown and the green gene in her but its very unlikely that you will get the other colour which is recessive (weaker) but it somtimes happens like me and you
look on the website i have posted it might help you, i learned about this a couple years back now and starting to forget it
2007-11-10 09:07:56 · answer #3 · answered by skellyskeldon 4 · 1⤊ 0⤋
i dunno, but have you ever seen an asian with blue eyes naturally, there has to be one out there, i am looking for them
2007-11-10 08:58:14 · answer #4 · answered by Anonymous · 0⤊ 1⤋