1. Multiple Alleles

2. Blood Type- codominance
Blood A is codominant to blood B
So it appears like this
A X B  AB blood type

3. Figure 10.12 Inheritance of Coat Color in Rabbits

4. Multiple Alleles When more than 2 different alleles control the trait.
Remember :
an allele is one form of a gene.
A gene is a segment of DNA that codes for a particular protein.
When more than 2 different alleles control the trait.
Coat color in rabbits is determined by a single gene that has at least 4 different alleles.
Different combination of alleles result in four different colors you see here

5. Human blood type- possible combinations
IA A
IB B
i O
IA & IB are codominant
IAIB  AB
IA I A A blood type
IA i
IB IB
IB i B blood type
ii O Universal donor i is recessive to everything

6. Multiple Alleles GENOTYPES IAIA IAi RESULTING PHENOTYPES Type A Type A
IBIB IBi
Type B Type B
IAIB
Type AB ii
Type O

7. Bell warm up What do you think they are talking about?

9. blood types

11. Bell Warm-Up 2-11-13 Show an example of a dihybrid cross
What is the ratio of phenotypes of a dihybrid cross?

12. T. Trimpe 2006 http://sciencespot.net/

13. What makes up our blood?
RED BLOOD CELLS (erythrocytes) – The most abundant cells in our blood; they are produced in the bone marrow and contain a protein called hemoglobin that carries oxygen to our cells.
WHITE BLOOD CELLS (leukocytes) – They are part of the immune system and destroy infectious agents called pathogens.
PLASMA – The yellowish liquid portion of blood that contains electrolytes, nutrients and vitamins, hormones, clotting factors, and proteins such as antibodies to fight infection.
PLATELETS (thrombocytes) – The clotting factors that are carried in the plasma; they clot together in a process called coagulation to seal a wound and prevent a loss of blood.

14. Blood Facts
The average adult has about FIVE liters of blood inside of their body, which makes up 7-8% of their body weight.
This red liquid is living tissue that carries oxygen and nutrients to all parts of the body, and carries carbon dioxide and other waste products back to the lungs, kidneys and liver for disposal. It fights against infection and helps heal wounds, so we can stay healthy.
There are about one billion red blood cells in two to three drops of blood. For every 600 red blood cells, there are about 40 platelets and one white cell.

15. How is our blood type determined?
Your blood type is established before you are BORN, by specific GENES inherited from your parents.
You receive one gene from your MOTHER and one from your FATHER.
These two genes determine your blood type by causing proteins called AGGLUTINOGENS to exist on the surface of all of your red blood cells.

16. What are blood types?
45%
40%
11% 4%
How common are the 4 blood types?
There are 3 alleles or genes for blood type: A, B, & O. Since we have 2 genes, there are 6 possible combinations.
Blood Types
AA or AO = Type A BB or BO = Type B OO = Type O AB = Type AB

17. Rh Factors A+ A- B+ B- AB+ AB- O+ O-
Scientists sometimes study Rhesus monkeys to learn more about the human anatomy because there are certain similarities between the two species. While studying Rhesus monkeys, a certain blood protein was discovered. This protein is also present in the blood of some people. Other people, however, do not have the protein.
The presence of the protein, or lack of it, is referred to as the Rh (for Rhesus) factor.
If your blood does contain the protein, your blood is said to be Rh positive (Rh+). If your blood does not contain the protein, your blood is said to be Rh negative (Rh-).
A+ A- B+ B- AB+ AB- O+ O-

18. How can blood be used as evidence?
Blood samples – Can be analyzed to determine BLOOD TYPE and DNA, which can be matched to possible suspects.
Blood droplets – Can be analyzed to give clues to the location of a WOUND, movement of a VICTIM, and type of INJURY.
Blood spatter – Can be analyzed to determine PATTERNS that give investigators clues to how a crime might have happened.

19. 14. Use the results shown to determine the blood type for each sample.
Blood Typing
14. Use the results shown to determine the blood type for each sample.
- = No Clumps
+ = Clump A B Rh
Blood Type: ___
To determine a person’s blood type, we add three different serums to blood samples and see if clumps form.
Clumps = Positive (+) No Clumps = Negative (-) What would the blood type be for this sample?
#13

20. - = absent + = present Blood TypingRh
1. Blood Type: ___ A B Rh
2. Blood Type: ___
Blood Typing
Use the results shown to determine the blood type for each sample. A B Rh
3. Blood Type: ___ A B Rh
4. Blood Type: ___ A B Rh
5. Blood Type: ___
- = absent
+ = present

21. A blood type (agglutination in A only)
Clumps in A only

22. B blood type agglutination in B only
Clumps in B only

23. AB blood type ( agglutination in both A and B)
Clumps in both A and B

24. O blood type (no agglutination in both A and B
No clumps

27. Example: what blood type is this?

28. Blood Typing A A Rh Rh A B B Rh A A Rh B Rh B B 2. Blood Type: ___

31. Blood typing Lab

32. Lab Procedure Group 1 Go the Lab tables (7 stations) Group 2
Work on Review Sheet (white paper)
b. Know information on yellow paper.
*Use yellow sheet to write “Brain dump” information that CAN be used on TEST!!!
AFTER finish Groups 1&2
Computer-complete blood typing game on (section B of lab paper

33. STOP

34. Mr.Smith A Mr. Green B Mr. Jones AB Ms. Brown O
Ms. Williams A Mrs. Chaney B Mrs. Hill AB

35. Who committed the crime
Extra credit
Who committed the crime

36. Can be given to patients with type:
O+ A+ B+ AB+
O- A- B- AB-
O+, A+, B+, AB+ A+, AB+ B+, AB+ AB+
O+, A+, B+, AB+, O-, A-, B-, AB- A+, AB+, A-, AB- B+, AB+, B-, AB- AB+, AB-
Patients with Type:
Can receive type:
O+, O- O+, A+, O-, A- O+, B+, O-, B- O+, A+, B+, AB+, O-, A-, B-, AB-
O- O-, A- O-, B- O-, A-, B-, AB-

37. Polygenic
Poly means MANY So polygenic means many genes determine the trait

38. Some Traits Don’t Follow Simple Mendelian Rules:
Some traits are determined by more than one pair of genes.  These are referred to as polygenic, or continuous, traits.  (poly = many)
Example: Human height.  The combined size of all of the body parts from head to foot determines the height of an individual. 

39. Polygenic = many genes
Gene 1 Gene 2 Gene 3 Trait (height)

40. Polygenic Traits Traits controlled by 2 or more genes
Means having many genes
Example: wide range of skin color in humans occur partly because more than four different genes probably control this trait
AABBCCdarkest skin color
Aabbcc lightest skin color
Three genes are also involved in making the reddish- brown pigment in the eyes of fruit flies.

42. Quick Lab Line up according to skin tone Discussion:
What can you infer about your skin tone compared to the
student next to you
2. 4th student to you
3. Ms. Chaney’s and yours
Skin color is determined by many genes- therefore polygenic

44. Below is the spectrum of human hair color
Below is the spectrum of human hair color. How is this trait controlled genetically?

47. Multifactorial Means many factors
Both genetic and environmental collectively influence the phenotype
Example: height and weight in humans
Genetics determine how tall you can be but diet and exercise can influence change
Example 2: color of hydrangea depends on PH

48. Some Traits Don’t Follow Simple Mendelian Rules:
Some genes are not expressed unless the right environmental factor is present.
For example, you may inherit the genes that are responsible for type 2 diabetes but never get the disease unless you become greatly overweight, persistently stressed psychologically, or do not get enough sleep on a regular basis. 

49. Some Traits Don’t Follow Simple Mendelian Rules:
Similarly, the genes that cause the chronic autoimmune disease, multiple sclerosis, may be triggered by the Epstein-Barr virus and possibly other specific environmental stresses. 
New research suggests that exposure to the sun in childhood can provide some protection from developing MS. So, people who grow up in tropical and subtropical regions of the world have significantly lower rates of MS as adults.

50. Important!!!!
Hemophilia and color blindness are examples of sex linked
Rabbit eye color and blood types – multiple alleles
Human skin color- polygenic
In sex linked:
Mothers can pass traits to sons and daughthers
Fathers can pass only to daughter (one x chromosome from dad)

52. B = black R = orange (Both are dominant) BR = calico
In cats, the gene for calico (multicolored) cats is codominant. Females that receive a B and an R gene have black and orange splotches on white coats. Males can only be black or orange, but never calico.
B = black R = orange (Both are dominant) BR = calico
Show the cross of a female calico cat with a black male cat.
1. What is the probability of getting a black male kitten? _________
2. What is the probability of getting a calico male kitten? _________
3. What percentage of getting a black female kitten? _________
4. What is the probability of getting a calico female kitten? _______
5. Why can male cats never be calico? _____________________

53. Genotypic ratio: ____________ Phenotypic ratio: ___________
Practice problem 1:
Longhorns may be white (CWCW), red (CRCR) or roan (CRCW). Roan longhorns have a mixture of both white hairs and red hairs.
Is this complete dominance, incomplete dominance, or codominance? ____________
What genotypic and phenotypic ratios would result if a roan longhorn mated with a white longhorn?
Genotypic ratio: ____________
Phenotypic ratio: ___________

54. What are the chances of these two longhorns having a roan offspring

55. Practice problem 2:
A naturalist visiting an island observes a species of small bird with three distinct types of beaks. Those with short, crushing beaks (BB) consume hard shelled nuts, those with long, delicate beaks (bb) pick the seeds from pine cones, and those with intermediate beaks (Bb), consume both types of seeds though they are not as good at either.
Is this complete dominance, incomplete dominance, or codominance? ____________
What genotypic and phenotypic ratios would result if a long- beaked bird mated with a short-beaked bird?
Genotypic ratio: ____________
Phenotypic ratio: ___________

56. What are the chances of these two birds having a short-beaked bird?

57. Genotypic ratio: ____________ Phenotypic ratio: ___________
Practice problem 3:
The ability to taste the chemical PTC is determined by a single gene in humans. People that are heterozygous for this allele can taste PTC. People that are homozygous recessive can not taste PTC.
Is this complete dominance, incomplete dominance, or codominance? ____________
What genotypic and phenotypic ratios would result if two heterozygous tasters were to marry?
Genotypic ratio: ____________
Phenotypic ratio: ___________

58. What are the chances of this couple having a “taster”? ________________

59. Birds can be blue, white, or white with blue-tipped feathers.
Co Dominance

60. Dogs can be either brown or black.
Complete Dominance

61. Flowers can be red, white, or pink.
Incomplete Dominance

62. Lady bugs can be red, yellow, or orange.
Incomplete Dominance

63. Corn can be black, yellow, or black and yellow.
Co Dominance

64. Humans can either taste a bitter chemical (PTC) or not taste it.
Complete Dominance
Humans can either taste a bitter chemical (PTC) or not taste it.

65. Humans can have the following blood types: A, B, AB, O
Co Dominance &
Complete Dominance

66. Phenotypic: 1 red , 2 roan, 1 white
A red bull is mated with a white cow. All of their offspring are roan-colored (coat with a mix of red and white hairs). * Cross two of the offspring, and report the phenotypic and genotypic ratios.
Co Dominance
Phenotypic: 1 red , 2 roan, 1 white
Genotypic: 1 RR, 2RW, 1 WW

67. Duh! You mate a great white with a seagull! Haha!!!
How do you get this?
Duh! You mate a great white with a seagull! Haha!!!

68. Humans have 46 chromosomes
44 are autosomal cells
2 are sex cells
Sex- linked inheritance means the trait is located on the X chromosome

69. Female needs 2 copies of recessive allele to have the trait
If only one trait, she will be a carrier
Mothers pass traits to sons and daughters
Male- need only 1 copy of recessive allele to express recessive trait (XY)
Fathers can pass only to daughter (one x chromosome from dad)

70. Sex-linked Inheritance
The allele for the trait is located on the X-chromosome and therefore the inheritance Pattern is slightly different in males and females XX  female (2X chromosomes) XY male (1X and 1Y chromosome)

71. Examples of sex-linked disorders
1. Colorblindness Inability to distinguish certain colors. 3 genes associated with colorblindness are located on X chromosomes
Males have just one X chromosome. Thus all X-linked alleles are expressed in males, even if they are recessive
For this to be expressed in female, there must be two copies of the allele, one on each X chromosome.
Color blindness is more common in males
Because fathers pass X to daughters. It may not show in daughter but can show later in grandsons

72. Colorblindness – in humans, colorblindness is a sex-linked trait and is recessive to normal vision.
C = normal c = colorblind
What is the sex of each of these people? Write either Male or Female on the blank below each
b. which are colorblind? _____________
c. which have normal vision? _________
d. Which has normal color vision even though she has the colorblind gene (is a carrier)? _________

73. Examples of sex-linked disorders contd:
Hemophilia is a genetic disorder passed from one generation to the next through the X (female) chromosome. 
blood does not clot normally.   
Although women transmit the disease, only men can exhibit it.  Women who carry hemophilia (carriers) have the gene on one of their X chromosome  Since the gene is recessive, they do not have the disorder. 
But if a male has the bad gene, then he will be a hemophiliac because there is no matching gene on his Y chromosome to be dominant to it. 
Females must have the gene on both X chromosomes to have hemophilia
Queen Victoria of England was a carrier of hemophilia and passed the disease to many of her descendants

74. Hemophilia is another example of a sex-linked disorder
Hemophilia is another example of a sex-linked disorder. People with hemophilia have blood that does not clot normally. Therefore, when they get a cut, they cannot stop bleeding. The gene for hemophilia is recessive.
H = normal h = hemophilia
Draw a punnett square for this cross: A homozygous normal female mates with a male with hemophilia.

75. Muscular Dystrophy Progressive weakening and loss of skeletal muscles
The disease, which almost exclusively affects males, begins in early childhood and usually causes death before adulthood.

76. Question
Why do males exhibit (show) traits passed on to them by their mothers?

77. Answer
Males have one X chromosome. So all X-linked alleles are expressed in males even if they are recessive.

78. In fruit flies, eye color is a sex linked trait.
R = red r = white
Draw a punnett square for this cross: A red-eyed male mates with a carrier female.
What is the probability of having a white-eyed male? ____________
What is the probability of having a white-eyed female? _____________
If this cross produced 200 flies, about how many would be white-eyed males? _______________