Expert: Florence M Rollwagen - 7/14/2008

Question
hello, I always wanted to have blue eyes. My father and both of his parents
had blue eyes. My mom has hazle eyes and my brother has blue eyes. I
have light brown eyes. My husband and both of his parents have brown eyes.    
What can I do to make sure that my child gets blue eyes? Thank you in
advance for your answer.

Answer
Hi Lina: Thanks for your question.

You cannot select the color of your baby's eyes because the outcome of fertilization will always be random.

You can, however, calculate the statistics of eye color given the genetics of you and your husband.

Your father has blue eyes, your mother hazel.  Your brother inherited a blue allele from his father and a blue allele from his mother.

You inherited a blue allele from your father and a hazel allele from your mother.  You have a 50:50 chance of donating a blue allele to your child.

Your husband has brown eyes and both his parents have brown eyes.  It is unlikely (but not impossible) that there are blue alleles in his genome.  Even if he has one blue allele (recessive like yours) his chances of donating a blue allele are 50:50 (just like yours).

So a chance of 1 in 2 multiplied by a chance of 1 in 2 gives us a chance of 1 in 4 for the baby to have blue eyes.

Actually, eye color is governed by many genes, each one donating a small increment, so it never works out 50:50.

Sorry I couldn't help you, it's just statistics.

Please write back if you have more questions.

FM Rollwagen, PhD