incomplete dominance
DESCRIPTION
Incomplete Dominance. Neither allele is dominant over the other Heterozygous offspring have a phenotype that is somewhere between the two. Incomplete Dominance. Incomplete Dominance. Homozygous red parent: RR crossed with Homozygous white parent: WW RR x WW - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/1.jpg)
Incomplete Dominance
Neither allele is dominant over the otherHeterozygous offspring have a phenotype that is somewhere between the two.
![Page 2: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/2.jpg)
Incomplete Dominance
![Page 3: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/3.jpg)
Incomplete Dominance Homozygous red parent: RR
crossed withHomozygous white parent: WW
RR x WW yields heterozygous offspring
RW that are pink
![Page 4: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/4.jpg)
Incomplete Dominance
![Page 5: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/5.jpg)
Codominance
Both alleles contribute to the phenotype
Heterozygous offspring express both alleles
![Page 6: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/6.jpg)
Codominance
X
![Page 7: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/7.jpg)
Codominance: A black chicken crossed with a white chicken results in a speckled chicken
![Page 8: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/8.jpg)
CODOMINANCE: ABO BLOOD TYPES
Blood type depends on the presence or absence of certain carbohydrates on the surface of red blood cells
3 alleles are possible: IA IB i
![Page 9: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/9.jpg)
ABO BLOOD TYPES IA and IB are codominant to each other
when they are paired.
i allele is recessive to both IA and IB
![Page 10: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/10.jpg)
ABO Blood Groups
![Page 11: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/11.jpg)
ABO Blood Groups
![Page 12: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/12.jpg)
ABO Blood Types Blood typing is actually far more
complicated than “A”, “B”, and “O” ABO are the MAJOR antigens There are also MINOR antigens
Rh factor: “+” or “-”
![Page 13: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/13.jpg)
ABO Blood Types
![Page 14: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/14.jpg)
ABO Blood Types
![Page 15: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/15.jpg)
ABO Blood Types
![Page 16: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/16.jpg)
ABO Blood Types Why is it important to get the right
blood type when getting a transfusion? Transfusion Reactions
Immune system (antibodies) will attack cells that have an antigen that the body doesn’t recognize as “self”
![Page 17: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/17.jpg)
Transfusion Reaction
![Page 18: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/18.jpg)
Multiple Alleles
More than 2 possible alleles exist in a population
![Page 19: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/19.jpg)
Multiple AllelesCoat color in rabbits: there are at least 4
different alleles C = full color (dominant to all other
alleles) c (ch) = chinchilla c (h) = himalayan c = albino (recessive to all other alleles)
![Page 20: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/20.jpg)
Full color rabbit
![Page 21: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/21.jpg)
Chinchilla rabbit: partial defect in pigmentation
![Page 22: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/22.jpg)
Himalayan rabbit: color in only certain parts of body
![Page 23: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/23.jpg)
Albino rabbit: no color; recessive to all other alleles
![Page 24: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/24.jpg)
Polygenic Traits
Traits that are produced by the interaction of more than one different genes
![Page 25: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/25.jpg)
Polygenic Inheritance For example: coat color in Labrador
retrievers is a result of interaction of 2 different genes.
![Page 26: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/26.jpg)
Polygenic Inheritance
Example: comb shape in chickens is a result of interaction between 2 different genes.
![Page 27: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/27.jpg)
X-Linked Inheritance Early 1900’s
Thomas Morgan’s fruit fly studies
![Page 28: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/28.jpg)
X-Linked Inheritance
![Page 29: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/29.jpg)
X-Linked Inheritance More than 300 human traits are X-
linked. Most common X-linked recessive
disorders: Hemophilia Red-green colorblindness Duchenne muscular dystrophy Adrenoleukodystrophy (seen in the
movie Lorenzo’s Oil)
![Page 30: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/30.jpg)
BARR BODIES Barr body is found only in females It is a darkly staining area in the
nucleus of a cell that represents an inactivated X chromosome
One X chromosome is randomly inactivated
![Page 31: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/31.jpg)
Barr Body
![Page 32: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/32.jpg)
Barr Body
Do you see the Barr body?
![Page 33: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/33.jpg)
Barr Body: X inactivation Calico cat
Generally all females Have one X chromosome coding for for
gold color, and one X chromosome coding for black color
Color pattern shows how one X chromosome in each cell is randomly inactivated
![Page 34: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/34.jpg)
Calico Cat There have been instances of male
Calico cats found How could this happen?
![Page 35: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/35.jpg)
Male Calico cat? HINT: Male calico cats are sterile
![Page 36: Incomplete Dominance](https://reader035.vdocuments.us/reader035/viewer/2022062520/56815c12550346895dc9eefe/html5/thumbnails/36.jpg)
Male Calico cat? Answer: Male Calico cats have XXY
chromosome configuration A Klinefelter’s cat? Yup, it happens.