FACT 1: The eye color results are due to the genes inherited from the parents. Genes exist in two conditions as dominant and recessive. The gene governing the brown color is found to be dominant.
FACT 2: The gene that governs the brown color of the eyes overrides the other genes which are responsible for determining other colors.
FACT 3: The gene meant for blue eyes is recessive. The genes that determine blue eyes will dominate their expression only when the genes for other eye colors are not present or not expressed.
FACT 4: The brown-eyed parents might transfer their respective recessive gene to the child where the child will have both the alleles of the gene as blue eye determinants. In this case, the brown-eyed parent might give birth to a child with blue eyes.
FACT 5: The brown-eyed parents might have a blue-eyed child due to the change in the blue gene during the DNA copying or DNA recombination processes occurring in the germ cells.
FACT 6: The eye color of the baby cannot be determined just after birth. Many times it might happen that the baby is born with blue eyes that gradually the color darkens. The green-colored eyes or gray-colored and other colors will result when all of those gene expressions are mixed.
FACT 7: A person might have blue eyes if he or she has Caucasian relatives in the past or if the person had a mutation in the gene that determines the eye color.
FACT 8: There is a disorder called Waardenburg syndrome where the person will have two different colored eyes. Blue eyes can also result due to this syndrome.
FACT 9: If the parents have the genes as Bb and BB (“B” for brown eyes and “b” for blue eyes), there is no chance for the children to have blue eyes.
FACT 10: If both parents have Bb type genes, then one of their children will have blue eyes.