Hemophilia Jessica Pinto Ben Hughes Sai Mandalapu February 1, 2010 Period 2

Hemophilia… What’s That? Hemophilia is spontaneous bleeding Bleeding can occur from: Stress Mild or greater trauma (sports, etc.) Before or after surgery Symptoms: Blood clotting improperly, if at all. Easily recognizable in childhood It was considered the “royal disease” because Queen Victoria had it and passed it through her family; the Russian royal family at the time also had it.

What chromosome is the disorder located on? It is contracted/passed down through the X-chromosome.

Mode of Inheritance It is passed through the X-chromosome. Men have it, and are affected by it (XY) Women are carriers (XX)

Alleles? Every person has two alleles per gene. Dominant alleles are represented by “big” letters. RR, Rr Recessive genes are represented by “little” letters. rr

Punnet Square GG Gggg Gg Dark Green: Homozygous Dominant Green-Yellow: Heterozygous Dominant Yellow: Homozygous Recessive G G g g

Punnet Squares Ratios: 1 GG : 2 Gg : 1 gg Percentages: 25% GG : 50% Gg : 25% gg

Punnet Squares GGGg ggGg A “Big G” represents the dominant allele, Green. GG ; Gg A “Little g” represents the recessive allele, Yellow. gg g G g G

Probability GGGg gg The probability of this punnet square, is that one of the children is affected with hemophilia, depending on the gender of the child, one of them would have it and the other would only be a carrier, and the final child would only be a carrier. G G g g

Student Practice GGGg gg Gg G g Genotype: Ratio: 3 Green, 1 Yellow Percentage: 75% Green, 25% Yellow Phenotype: Ratio: 1GG, 2Gg, 1gg Percentage: 25% GG, 50% Gg, 25% gg

Pedigree Chart Key: Circle: Female Square: Male Shaded in: affected Not shaded: not affected Half shaded: carrier

Student Practice Key: Circle: Female Square: Male Shaded in: affected Not shaded: not affected Half shaded: carrier When is the female ever completely affected? Why is the male never a carrier? When are both not affected?