Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Blue-eyed Babies
Name: Jill
Location: N/A
Country: N/A
Date: N/A

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?


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.


Click here to return to the Biology Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory