A normal man &normal femail who son has red color blindness&kleinfeltersyndrome?

Answer 1

The son must be XbY for colorblindness, having gotten the allele for colorblindness on the X-chromosome from his Mom and the Y-chromosome from his Dad.

Klinefelter's syndrome is a trisomy: XXY. This could have resulted from nondisjunction in his mother, producing an egg that was XX instead of the normal egg which would be X.

XX joined with Y from the Dad would yield XXY, the boy with Klinefelter's syndrom.

It's also possible that the nondisjunction happened in the father, resulting in a sperm that was XY instead of Y. Then the boy got X from Mom and XY from Dad ---> XXY.

Answer 2

http://en.wikipedia.org/wiki/Kleinfelter%27s_syndrome

http://en.wikipedia.org/wiki/Color_blindness