1. Albinism A Genetic Disorder
Gabby and Stef A.
Period 6/7

2. About Albinism
Albinism is a disorder that affects the skin, hair, and eyes.
The hair, eyes, and skin usually have no pigment(color).
Symptoms:
No color in hair, skin, or iris of the eyes.
Lighter hair color and skin.
Patch, or missing skin color.
Interesting Facts:
Sometimes the eye color can change
People with albinism are sensitive to light (photophobic)
Other forms of Albinism are involved with symptoms of other
disease

3. Albinism’s Chromosome
OCA1 is located in Chromosome 11 .
Chromosome 11
Location of OCA1 on Chromosome 11

4. Albinism is Autosomal Recessive
Mode Of Inheritance
Albinism is Autosomal Recessive
Autosomal Recessive- Two copies of the abnormal gene must be present in order for the disease or trait to develop.

5. Alleles
Allele- Alternative forms of a gene for each variation of a trait of an organism.
One from mother, One from Father.
Recessive- aa
-Trait that can be masked by the dominant form of a trait.
Dominant- AA
Observed trait that masks the recessive form of a trait.

6. Punnett Squares A a a a AA Aa aa Aa A A a A

7. Punnett Squares and RatiosAA Aa aa
Ratios-
AA | Aa | aa A a
Percentages-
25% % %
AA | Aa | aa

8. AA aa Aa A a Punnett Squares A a A = Dominant Allele
a = Recessive Allele AA Aa aa A
Genotype: In Gene
AA = Homozygous
Dominant(not albino)
Aa = Heterozygous dominant(not albino)
aa = Homozygous recessive(albino) a
Phenotype:
AA= Not albino
Aa = Not Albino but Gene Carrier
aa= No Melanin/Albino

9. AA aa Aa A a Punnett Squares A a Phenotype- Physical (Seen) Ratios:
1 Albino ;
3 Not Albino
Percentages:
25% Albino ; 75% Not Albino AA Aa aa A a
Genotype- Genes (Genetic)
Ratios:
1AA : 2Aa : 1aa
Percentages:
25%AA: 50%Aa: 25%aa

10. Aa aa Aa aa a a Student Practice! A a Genotype: Ratio: 1 : 1 : 2
Percentage: 25% : 25% : 50%
Phenotype:
Ratio: 2 NO Albinism; 2 Albinism
Percentage: 50% Albinism ;
50% No Albinism Aa aa a Aa aa a

11. Pedigree Gabby Tyler Jessica Kevin Steph Ventura Yvenson Stef Emma
Jeff
Purple- Fine. NO ALBINISM!
Pink- Not fine. ALBINISM PRESENT!

12. Student Practice Gabby Tyler Jessica Kevin Ventura Steph Yvenson Stef
Key
Circle: Female
Square: Male
Pink: Albinism
Purple: Non-Albinism
Gabby
Tyler
Jessica
Kevin
Ventura
Steph
Yvenson
Stef
Emma
Jeff
Questions:
What will happen to the child if both of the parents have recessive genes?
What would the result be if Emma and another recessive male had children?
Would the child have albinism or not?

13. THE END 