|MadSci Network: Genetics|
I will try my best to explain this in a non-biology way. If this needs expanding, let me know. From my research into this topic, it would appear that it is not possible for two blue eyes parents to have a green eyed child, except, that is, in the case of a mutation which has caused the child to "break the rules". It is also possible that there are, in fact, many more genes involved and that green eyes can lay dormant and shock us when they appear. If one, or both, of the parents have "bluey green" eyes, then this is what may be goingn on. Here is what most scientists think at this time. Eye colour is managed by two gene, these being the bey2 and gey genes. The bey2 gene is concerned with brown and blue and the gey gene is concerned with blue and green. In order for somone to have blue eyes, both copies of both of these genes must show blue.ie, there will be no trace of brown eye or green eye genetic material in person's chromosomes. If both parents have blue eyes, then there is no way for any genetic material for brown or green eyes to be passed to their children. So all children will have blue eyes. So, in summary, it is generally considred impossible for parents with blue eyes to have anything but blue eyed children. (Please see the MadSci disclaimer: http://www.madsci.org/info/disclaimer.html
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