1. Complex Inheritance Patterns
Kline
Biology

2. 1. Simple Recessive Also called “autosomal recessive”
Trait/Disease is carried on the recessive allele
Must inherit trait/disease from both parents
Ex/ Cystic fibrosis
CC – Normal (not afflicted)
Cc – Carrier (has the allele for the disease, but no symptoms)
cc – Afflicted (has the disease)

3. Simple Recessive
If two heterozygous carriers for Cystic Fibrosis had a child, what would be the likelihood that their child would inherit the disease? Draw a Punnett square and write the probability.

4. 2. Simple Dominant Also called “autosomal dominant”
Trait/Disease is controlled by a dominant allele
Individuals only have to receive one dominant allele from one parent to have the disease.
Very rare
Appears later in life – Most often these individuals pass on the disease to their children before they know they have it.
Ex/ Huntington’s Disease

5. Simple Dominant
If a normal homozygous recessive woman and a man who was heterozygous for Huntington’s had 4 children, what would be the probability of their children’s genotypes?

6. 3. Sex-linked Trait/disease is carried on the X or Y chromosome
Most of these genes are carried on the X chromosome so they mostly affect males
Ex/ Male pattern baldness, Fur color in cats, Hemophilia (a blood clotting disorder)

7. Sex-linked
In cats, the trait for orange and black fur is carried on the X chromosome. Calico cats are black and orange and can only be female. Explain why male cats can not be calico.

8. Sex-linked
Draw a punnett square for a heterozygous female carrier and a normal male. What is the genotypic ratio of their children?
XH X – Mother
X Y – Father

9. 4. Incomplete Dominance
A heterozygous individual has an “intermediate” phenotype.
Ex/
RR – red flower
WW – white flower
RW – pink flower

10. Incomplete Dominance
In beta fish, green (GG) and steel blue (BB) and incompletely dominant traits. A royal blue fish (GB) is an intermediate color. If two royal blue fish mated, what would be the ratio of their offspring?

11. 5. Codominant A heterozygous individual expresses both traits. Ex/
BB – Black Feathers
WW – White Feathers
BW – Black and White Feathers
If you crossed a purebred black with a purebred white, what would be the genotypes and phenotypes of their offspring?

12. Codominant RR – Red Flower WW – White Flower RW – Red and White Flower
If you crossed two heterozygous flowers, what would be the ratio of their offspring?

13. Codominant
Blood type is a codominant trait. A type blood and B type blood are equally dominant. O type blood is recessive. If someone receives an A allele and a B allele, they will express both phenotypes and have type AB blood. A child has O type blood. His mother has A type blood and his father has B type blood. Could those be his biological parents? Explain.

14. RH Factors in Blood Type

15. Who can give blood to who?

16. 6. Multiple Alleles
When there are 3 or more alleles that exist in a population for a particular gene.
Ex/ Rabbit Fur color
In a population of rabbits, there is an allele for solid color fur, chinchilla colored fur (speckled), Himalayan fur (certain parts of the body), and albino fur.
Each individual rabbit only receives 2 alleles, but there are 4 possible alleles in the entire gene pool of rabbits.

17. Multiple Alleles

18. 7. Polygenic Traits A trait that is controlled by 2 or more genes.
Ex/ Eye color

19. Polygenic Traits
Skin Color

20. 8. Epistasis
An epistatic gene interferes with the expression of other genes.
Causes albinism