Codominance

In Codominance the organisms have 2 different phenotypes but their offspring show a third phenotype in which both traits show up in the offspring. Neither trait is dominant nor reccesive so then they both show up equally in the offspring. An example of codomincance in humans is type AB blood because both A and B show up together in the cell. Not only can there be codominance in blood type but it can also occur in the eyes. [|Codominance]- This is a widget video that shows who could be the child's dad by figuring out the blood types. [|Codominance Link] This Link has basic information about codominance as well as real world examples and Punnet squares. - Jason Van Winkle Many people could have a mixture of their parents eye color or could even have on eye the color of their father and the other the color os their mother. This is known as heterochromia. Heterchronmia is the difference in the color of eyes, skin, or even hair. It is usually caused by the lack of melanin. It can be inherited by genetic mosaicism, injury, or disease. Codominance is the relationship between 2 alleles of a gene type. When a dog with white fur mates with a dog with black fur their offspring will have a mixture of white and black colored fur. The same thing goes for a white cat and a tan cat. [|Heterochronmia Link] This link goes more in depth on heterochronmia and how it works. --Kelsie

Codominance and incomplete dominace are very similar but are also very different. Many people get these two things very confused but if you really think about it its quite easy to understand. In Incomplete Dominance the genotype is heterozygous just like that in Codominance but the color of the offspring is different. In Incomplete Dominance a white and red plant produce a pink flower. If it was Codominance the flower would be a mixture of white and red but that is not the case so it would have to be Incomplete Dominance. Sometimes the difference comes down to something that can only be seen at a molecular level.

[]--- This is a link that you can visit to read about the difference between Codominance and Incomplete Dominance. Once your done reading about it there are questions at the bottom of the page over what you just read.

Oculocutaneous Albinism is just like heterchromia were the pigment melanin is not produced so their can be a defect in the offspring. This disease is linked to codominance because not only can your eyes be different colors but your skin and hair can also be different. The body lacks the enzyme tyrosanine and then it cannot break down dihydroxyphenyalanine into the melanin you need. It is more dramatic in African Americans but can happen in any ethnic group. There is also something called sectoral heterchromia which is where the person has two different colored eyes with a spot of a different color in there. They think that it could be linked to Waardenburg syndrom and Hirschsprung's disease which is a disease that happens in the large intestine that stimulates the muscle that pushes the stool through the intestine and out of the body. [|oculocutaneous albinism]- Boone, This site tells about what this thing is, how common it is and more!

Some symptoms of Hirschsprung's disease in babies are green or brown vomit, explosive stool after the doctor inserts their finger into the baby's rectum, swelling of the stomach, gas, and bloody diarrhea. Hirschsprung's disease can't be treated through surgery. The surgeon will just remove the part of the large intestine that doesn't have the nerve. Ostomy surgery is where they take out the part of the intestine that lacks the nerve and connects the healthy part to a hole in the abdomen where there is a pouch that collects the stool. The pouch needs to be emptied several times a day. Waardenburg syndrome is an inherited disease that characterizes different levels of hearing loss and change in hair and skin pigment. People with the hair pigment disorder may just have a patch of random white hair (or skin) or premature gray hair at age 12. They might also have a while nasal root, a low frontal hair line in the front and their eyebrows might connect. 50% of people with this disorder are deaf. There is no real treatment for this syndrome. If they have seeing problems they could have surgery. Waardenburg syndrome doesn't usually affect the mind.

PKU is a codominant trait that must be passed on by both parents for the child to have it. PKU is the lack of pigment color and melanin. Sickle-Cell is a genetic disease that affects the hemoglobin of the red blood cells. Hemoglobin is reguarly ball-shaped but sickle-cell makes them form in long strands. When the molecules become this shape it is very hard for them to get through the tiny blood vessels in the body. Eventually they end up getting stuck and the person will have a blood clot. The shape of the molecules is controlled by two alleles one is Normal Hemoglobin and the other allele is Sickle-Cell. Normal people have two alleles of the Normal Hemoglobin but people with sickle-cell have atleast two sickle-cell alleles in theie genotypes. There can also be a heterozygous mixture where only 50% of the red blood cells are shaped like that. This happens when the offspring recieves both alleles like in codominance.



Codominance occurs all the time with humans and with plants. Codominance is a very interesting subject and there are some things we learned about that I had no clue even existed. Codominance happens in alot of organisms but when it happens it can be very noticable. By: Dr. Alex, Dr. Eric

[]- this is a game that lets you pick what two objects or organisms you want to cross, and then by the end of the game it will give you questions about what the offspring will look like. -Kayla

[] This website tells you more about hirschsprung disease. It gives you the symptoms, definition, and even causes. I think this disease is interesting because I have never heard of it before, and it is truley sad that people have to go through this. -Tasha

=Work Citied=

[|CoDominance]

[|Codominance Wiki]

[|Codominant Genes]

[|Incomplete and Codominance]

[|Reccessive Codominance]

[|COdominant Genetic Traits]