1. Hemophilia By: Abijah Minton Alfredo Sugawara Brandon Abad

2. Summary of Hemophilia Summary of Hemophilia  Hemophilia is a disorder where your blood doesn’t clot.  It is a recessive trait.  If a mom doesn’t have the gene for hemophilia and the father does, their son will not carry the trait for hemophilia but their daughter will.  Symptoms of hemophilia are excessive bleeding. Other people may experience life threatening hemorrhages with common injuries.

3. What Chromosome is your disorder located on?  This disorder is located on the x chromosome.

4. Mode of Inheritance  Someone would acquire hemophilia from sex linked traits.  If a trait is sex linked, then a gene is only carried by the male or female parent. Not by both.

5. Explaining Alleles  An allele is any of several forms of a gene, usually arising through mutation, that are responsible for hereditary variation.  Alleles come from a female and male parent.  RR stands for dominant alleles. rr is a recessive allele. Rr is the dominant gene over the recessive gene.  The dominant gene produces the same phenotype in the organism whether or not its allele identical.  The recessive gene produces its characteristic phenotype only when its allele is identical.

6. Probability of Passing Down Hemophilia HHHh hh H h H h hh h H hh

7. Probability Using Ratios And Percentages Ratios 2 : 2 Hh : hh Percentage 50% : 50% 50% Hh : 50% hh Hh hh

8. Explanations  A capital H means that the allele for Hemophilia is dominant, where as a lowercase h means recessive.  HH: Hemophilia, Hh: Hemophilia, hh: Not Hemophilia  HH: Homozygous Dominant, Hh: Heterozygous Recessive, hh: Homozygous Recessive

9. Genotype And Phenotype Probability Phenotype – Ratio: 2 Hemophiliacs to 2 Non- Hemophiliacs – Percentage: 50% to 50% – Percentage: 50% to 50% Genotype – Ratio: 2 Hh to 2 hh - Percentage: 50% Hh to 50% hh - Percentage: 50% Hh to 50% hh

10. Student Practice Hh H h HH Hh hh Genotype: Ratio: Percentage: Phenotype: Ratio: Percentage: 1 : 2 : 1 25% : 50% : 25% 3 : 1 75% : 25%

11. Hypothetical Pedigree Key Female Hemophiliac Female Male Hemophiliac Male

12. Student Practice Key Female Hemophiliac Female Male Hemophiliac Male 1. Out of the second generation siblings, what is the ratio of hemophiliacs to non-hemophiliacs? 2. How many females in this pedigree have hemophilia? 3. How many males in this pedigree have hemophilia? 2 : 1 3 2