1. When Something Goes Wrong…
A Look at Genetic Disorders

2. Principles of Inheritance
Pedigree chart (P. 206)
-Used to show patterns of trait transmission in a family.
HCM - hypertrophic cardiomyopathy

3. Types of Inheritance
A Human chromosome set can be broken into two groups:
1. Sex chromosomes
X & Y
2. Autosomes
The other 22 pairs!
All 46 can be analyzed using a Karotype

4. Types of Inheritance Autosomal Recessive Inheritance
Both parents heterozygous
Trait may skip a generation
Males and females affected equally
Eg. Light eye colour & Albinism

5. Types of Inheritance 2. Autosomal Dominant Inheritance
½ of children of affected parent are expected to be affected.
Trait does not skip generations.
Males and Females affected equally.
Eg. Dark eye colour, Huntington’s Disease.

6. Types of Inheritance 3. X-Linked Recessive Inheritance
Recall (from yesterday)…
Mostly males!
Trait skips generations
Eg. Colour blindness, Hemophilia
TRY THIS!
“Tracking the Hemophilia Gene” worksheet

7. Genetic Disorders Are the result of Mutations…
A change in the genetic code.
Most are recessive alleles so harmful
effects are masked by a dominant gene.
Visible health problems at birth are called “congenital defects”.
The defects can be a result of genetic and environmental factors.

8. Genetic Diseases – P. 205 Two Types: Single Gene defect
-Sickle Cell anemia
-Cystic Fibrosis
-Huntington’s Disease
-Muscular Dystrophy
-Hemophilia
-Colour blindness
Chromosomal defect
-Cri-du-chat syndrome
-Fragile X
-Down Syndrome
-Klinefelter & Turner Syndromes

9. Single Gene Defects

10. Chromosomal Defects

11. Homework!
Page 200 #1, 5
Page 209 #1,2,3,5

12. A look at DNA Technology
CSI Explained
A look at DNA Technology

13. Be a “Genetic Detective”…
TRAIT
YOUR
PHENO
GENO
MOM’S
DAD’S
SISTER #1 d D

14. Be a “Genetic Detective”… Solution
TRAIT
YOUR
PHENO
GENO
MOM’S
DAD’S
SISTER #1 d dd D Dd
Dd or DD

15. DNA Technology
DNA profiling uses Gel Electrophoresis to compare DNA samples to “find a match”.

16. Gel Electrophoresis Most genes are similar among people.
However, our ‘Junk’ DNA is different.
Therefore we all have a unique DNA sequence or ‘DNA fingerprint’.
Except for identical twins of course!

17. Gel Electrophoresis
A slab of agarose gel is hooked up to a power source.
The DNA sample is treated with restriction enzymes to cut it into pieces of varying lengths. (These lengths are different in everyone)

18. Gel Electrophoresis
The DNA sample is placed the negative end of the gel and migrates towards the positive end.
Small pieces move faster and farther through the gel than larger ones.
This creates a unique pattern for an individual.
The pattern is transferred to an X-ray film.
Look for a MATCH!

21. I’ll see you in court…

22. DNA databases…
Who’s DNA should be included?

23. DNA Extraction LAB