alzheimer's disease kai lin chase upshaw january 27, 2010 period 09-10
TRANSCRIPT
Summary of Alzheimer's
• It’s a progressive disease of the brain.
• Mainly characterized by memory loss.
• It was first recognized in the early 1900s.
• Symptoms Personality changes Frequent and unexplained mood swings Difficulty/inability to do things they once where
able to do Temporary confusion while in normal
environment Difficulty finding words and keeping casual
conversation
Where does it come from?
• Alzheimer's is still not entirely explained.
• The risks of have Alzheimer's are 11% if neither parents have Alzheimer‘s 36% if one parent has it 54% if both parents have the disease 40%-50% if an identical twin has it
• 68% of those with Alzheimer‘s in the U.S. are women.
• 85% of those with Alzheimer‘s in the U.S. are white.
What Are Alleles?
• Alleles is another way of saying genes.
• Alleles come from your parents.
• There are dominant alleles, represented with a capital letter, and recessive alleles, represented with lowercase letters.
• EXAMPLE: WW, ww, Ww
• Dominant alleles have more influence than recessive alleles.
Punnett Squares
a a
A Aa Aa
a aa aa
A a
A AA Aa
A Aa Aa
a a
a aa aa
a aa aa
a a
A Aa Aa
A Aa Aa
Parent #1
Parent #2
Dominate Allele
Recessive alleleHomozygous Dominant
Heterozygous Dominant
Homozygous Recessive
Ratios and Percentages
Ratios
2 : 2
2 Aa : 2aa
Percentages
50% : 50%
50% Aa : 50% aa
A a
a Aa aa
a Aa aa
What do the letters in the Punnett Square mean?• AA or Aa- Dominant allele (Alzheimer’s)
• aa- Recessive allele (No Alzheimer’s)
• Phenotype (What you see)
AA- Alzheimer’s gene
Aa- Alzheimer's gene (carries the non-Alzheimer’s gene, but the Alzheimer’s gene dominates)
aa- Non-Alzheimer’s gene
• Genotype (What is in the genes)
AA- Homozygous Dominant (Alzheimer’s)
Aa- Heterozygous Dominant (Alzheimer’s)
aa- homozygous recessive (Non-Alzheimer’s)
Ratios and Percentages Cont.
• Phenotype
Ratio- 2 Alzheimer’s : 2 Non-Alzheimer’s
Percentage-
50% Alzheimer’s : 50% Non-Alzheimer’s
• Genotype
Ratio- 2 Aa : 2 aa
Percentage- 50% Aa : 50% aaA a
a Aa aa
a Aa aa
Student Practice
A a
AAA
a aa
Aa
Aa
• Genotype
Ratio1 AA : 2 Aa : 1aa
Percent25% AA : 50% Aa : 25% aa
• Phenotype
Ratio3 Alzheimer’s : 1 Non- Alzheimer’s
Percent75% Alzheimer’s : 25% Non-Alzheimer’s
Hypothetical Pedigree Chart
The white figures with the lines through them mean that the person died of something other than Alzheimer's Disease. The black figures with the lines through them mean that the person died of Alzheimer’s Disease. The black figures mean that the person has Alzheimer’s Disease while the white figures mean that the person does not have Alzheimer’s Disease.
More Student Practice
Circle- MaleSquare- FemaleHalf shaded in- Heterozygote DominantShaded in- Homozygote DominantNot shaded in- Homozygote Recessive
1. What is the percentage of people in the second generation that have Alzheimer’s Disease?
2. How many people have the recessive gene? Dominant gene?
3. How many people do you think will have the homozygote dominant gene? Why?