How do I know if my 22 month old daughter is color blind?

Q: My 22 month old daughter knows her ABCs, can count to 20, has a great memory, recognizes a large number of animals and insects by name... she is really smart! But I noticed that she cannot remember colors. She kind of guess them , but most of the time she's wrong. A friend asked me if she is color blind. How do I know if she is color blind or just not interested in learning her colors?

A: Genetic color blindness is much more common in boys than it is in girls as it is carried on the X chromosome and as girls are XX and boys are XY a girl would have to have two abnormal chomosomes to be color blind while a boy would only need one. A lack of red-green color vision is the most common type. That being said it is pretty unlikley that your daughter is color blind if she is consistently missing all of the colors. Most likely she has not reached the developmental milestone of color identification and I would not expect her to reach until she is between the ages of 3 and 4 years. Counting and reciting ABCs are much easier tasks for her brain to master as they are memorization of a pattern rather than identification. She will likely have trouble telling you what number comes after 16 without reciting from the number one or for the same reason. With time she will also master color identification. If you are still worried about color blindness there are cards used to identify color blindness that have a base color and a picture or number in another color and someone who is color blind would not be able to see the image.

Answered by Dr. Carrie M. Brown