Color Vision Deficiency Is a condition where the retina (eye) is unable to distinguish colors correctly It can either affect seeing the red and green (most common), blue and yellow, or all colors (monochromacy) 1 out of 12 men are affected and 1 out of 100 women have this condition

It is sex linked Genetic red-green color blindness affects men much more often then women because the genes for the red and green color receptors are located on the X chromosome of which men have one and women have two

 Meaning concerning characteristics that are determined by genes carried on the sex chromosomes (on the X chromosome in particular)  Genetic  Other modes of inheritance include:  Diabetes  Glaucoma  Macular degeneration  Alzheimer’s Disease  Parkinson’s Disease  Multiple Sclerosis  Chronic Alcoholism  Leukemia  Sickle Cell Anemia  Certain Medications used to treat heart problems, infections, and psychological problems  Aging  Chemical Exposure such as fertilizers

Each person has two alleles Come from our parents Capital letters are dominant and lower case letters are recessive genes D for color blindness dfor non color blindness Dd for carrier of color blindness The dominant gene and recessive genes carry the same traits, but the dominant trait overpowers the recessive

XDXD XdXd XDXD Y homozygous dominant heterozygous dominant homozygous recessive XDXDXDXD XDYXDY XdXDXdXD XdYXdY

1:2:11:2:1 Homozygous DominantHeterozygous DomHomozygous Res 25%:50%:25%

Phenotype D for color blindness d for non color blindness Dd for carrier of color blindness XDXD XdXd XDXD Y XDXDXDXD XDYXDY XdXDXdXD XdYXdY Genotype D for homozygous dominant (color blind) d for heterozygous dominant (non-color blind Dd for homozygous recessive (carrier of color blind gene)

Genotype -Ratios [3 with color blind gene : 1 without] -Percentages [75% with color blind gene: 25% without] XDXD XdXd XDXD Y XDXDXDXD XDYXDY XdXDXdXD XdYXdY Phenotype -Ratios [1 xdxD : 2 xDxD xDy : 1 xdy] - Percentages [25% xdxD : 50% xDxD xDy : 25% xdy]

XDXdXDXd XDXdXDXd XDYXDY XDYXDY XDXD XDXD XdXd Y

= normal vision male (healthy) = color blind male (bad) = normal vision female (healthy) = normal vision female with recessive gene (one bad one healthy)

= normal vision male (healthy) = color blind male (bad) = normal vision female (healthy) = normal vision female with recessive gene (one bad one healthy) Questions: 1.What caused the 3 nd generation boy to be color blind? Questions: 2.What caused the 2 nd generation girls to have one bad and one good gene? Questions: 3. Why is the 2 nd generation boy normal?

About 8% of all men are suffering from color blindness.8% of all men A father can’t pass his red-green color blindness on to his sons.can’t pass his red-green color blindness If a woman is red-green colorblind, all her sons will also be colorblind.all her sons will also be colorblind When using color correcting lenses you are wearing two differently colored lenses in your eyes.color correcting lenses More women than men are carriers of color blindnessMore women than men are carriers of color blindness, even though they are not colorblind themselves. Police officerPolice officer, firefighter, and airline pilot are the most famous jobs which require normal color vision. firefighterairline pilot Color blindness is also called Daltonism, after the scientist John Dalton.Daltonism MonochromacyMonochromacy—also called achromatopsia—means you have only one type of color receptors (cones) in your eyes.