Eye Color Explained

What most people know
about the inheritance of
eye color is that brown
comes from a dominant
gene (needing one copy
only) and blue from a
recessive gene (needing
two copies). University of
Queensland geneticist Rick
Sturm suggests that the
genetics are not so clear.
“There is no single gene
for eye color,” he says,
“but the biggest effect is
the OCA2 gene.” This gene,
which controls the amount
of melanin pigment
produced, accounts for
about 74 percent of the
total variation in people’s
eye color.