Question:
One of my students asked me the other day why all babies
are born with blue eyes, even though they are truly brown-eyed, once
their eyes change colour. What causes this phenomenon? Exposure to
air, maybe?
Replies:
Hi,
First of all not all babies are born with blue eyes. This is especially
evident in the Asian/ Indian continents.
The cause for the delay is nothing more than a delay in the enzymes that
bring on the darker color proteins. You are probably aware that eye color
is determined by more than one gene. The darker colors have blue coloration
as part of their make-up and that may be the only protein of the color
exposed at birth for many individuals. The proteins that give the darker
colors usually turn on within a year of birth and this timing varies with
individuals.
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