Eye color is one of those things that everyone recognizes. What color is his/her eyes? Blue eyes, green eyes, hazel eyes, brown eyes, and perhaps some shades in between are the basic colors. Your eye color is given to you by your parents. Mom and Dad transmit half of the information needed to make this determination. Once these halves are joined together in your DNA, they will determine which color comes shinning through.
As you now know, this determination is made by the message you carry on your DNA. A series of codons, which make up the "gene" for eye color, is strung along one of those chromosomes (DNA molecule). It has two sides...the one from Mom, and the one from Dad. Remember your dinning rooms? The one you stood in to image 3-D space is one side of this gene. Your bucket truck reaches out to the other side. If you are standing in your mother's dinning room, your father's dinning room would be on the other side. [the gene is the whole series of dinning rooms on both sides, stacked upon one another, running in opposite directions]
If Dad has blue eyes, and mom has brown eyes, brown eyes will win out every time if Mon only carries the brown eye message on both sides of her DNA. [Brown eyes are called dominate.] If Mom carries a brown eye/blue eye gene, then it is possible to transmit blue eyes to a child. [one blue side from Dad, one blue eye from Mom] The blue eye color has been called recessive. Each side of this genetic message is now called an "allele". This term is important to know as we continue in our understanding of using DNA for genealogy. The "allele value" is the number giving to one half of the genetic marker along the codon (genome). It is like spray painting your side of dinning rooms, and spray painting the other side a different color. Thus each side of the gene can be classified by an address (allele number). The side for "brown eyes" and "blue eyes" will be labeled by a number. When you order a DNA test today, you will be given a series of "allele values" as results. These are the places along your genes that have been tested. The results of a 12 marker test is given by a series of numbers which identify the "alleles" that were examined by the laboratory doing the test. Baby blue eyes any one?