What is the difference between dominant and codominant

Similarly, if our genotype had two blue Rs then we could expect that in all cases the flower petals will be blue since we only have blue Rs in the genotype. Now these three different dominance patterns change when we look at the heterozygous example. That's what makes these three patterns different. Now we're already familiar with the example of complete dominance, so if we said that the red R is dominant over the blue R then this would make the heterozygous phenotype a red flower for complete dominance.

Now what co-dominance is, is when the heterozygous phenotype shows a flower with some red petals and some blue petals. So it's when the two alleles are dominant together they are co-dominant and traits of both alleles show up in the phenotype. Now what incomplete dominance is, is when the heterozygous phenotype shows a mixture of the two alleles.

So in this case the red and blue flower petals may combine to form a purple flower. Neither allele is completely dominant over the other and instead the two, being incompletely dominant, mix together. So what did we learn? Well, if we assume the heterozygous genotype, red R, blue R, then there are three different dominance patterns that we might see for a specific trait. In complete dominance, only one allele in the genotype, the dominant allele, is seen in the phenotype. And this was the example with the red flower.

An uppercase letter e. A denotes a dominant trait or genotype and a lowercase denotes a recessive trait or genotype e. The genotype is a major factor that determines the phenotype physical or biochemical characteristics of an organism.

In the given example above, there could be three possible genotypes: AA , Aa , and aa. And based on the nature of these alleles, the condition may be homozygous or heterozygous. Homozygosity is the condition wherein the alleles on the locus are the same or identical e. AA or aa. In contrast, heterozygosity is the condition wherein the alleles occupying the same locus are different e. AA genotype is homozygous dominant whereas Aa , heterozygous dominant. The aa genotype is an example of homozygous recessive.

In genetics, dominance pertains to a gene or allele expressed over the other genes or alleles. There are three major forms: complete dominance , incomplete dominance , and codominance. When an individual inherited two dominant alleles e. AA or inherits at least one dominant allele e.

Aa , that individual will show the trait because of the presence of the dominant allele. In contrast, the individual lacking the dominant allele e. This is what occurs in the complete dominance and the resulting pattern conforms to the Mendelian inheritance.

Hence, the heterozygous organism Aa will have a trait similar to the homozygous dominant AA. Conversely, those that do not conform exemplify the non-Mendelian type of inheritance.

In non-Mendelian inheritance, the resulting phenotype of the offspring is different from the phenotypes of either parent. Codominance and incomplete dominance are examples.

This results in offspring with a phenotype that is neither dominant nor recessive. As for the incomplete dominance definition, this form of inheritance occurs when the phenotype is intermediate to the phenotype of the parents. An example of incomplete dominance is when a male white flower parent is crossed with a female red flower the offspring will be a plant that will soon bear pink flowers.

Codominance is different from incomplete dominance in the way that the former has both alleles manifesting the phenotypes whereas the latter produces an intermediate phenotype. Got a question about codominance? Share with us what you think. It implies that both dominant alleles are present and expressed together. This indicates type AB blood. Conversely, a genotype of ii means lacking such modifications on the H antigen and an indication of a type O blood.

In codominance, blood type AB implies that both dominant alleles are present and expressed together. In other animals, codominance is exemplified by a mix of coat colors in a progeny of parents with different coat colors.

In codominance, both alleles are expressed together in the offspring. If we cross a red flower and white flower that have a codominance inheritance pattern, the offspring would be flowers with red and white patches on them. Unlike incomplete dominance, where the two parent phenotypes are blended together into a new phenotype, in codominance, both parent phenotypes show up together on the offspring.

The most common example of codominance is the AB blood type. If a person with A type blood and a person with B type blood have a child, that child could have type AB blood where both phenotypes are fully expressed. When comparing codominance vs. Below are three Punnett squares, two for incomplete dominance and one for codominance. In the Punnett square below we are crossing a pure red flower RR with a pure white flower rr. Under incomplete dominance, all of their offspring would be pink Rr.

Under the complete dominance type of inheritance the type of inheritance you probably first studied when learning about genetics , all the offspring would be red flowers, since the red allele would be completely dominant over the white allele. However, as mentioned above, with incomplete dominance, the two parent phenotypes are blended together in the offspring. What happens when you cross two pink Rr flowers? Half the offspring would be pink Rr , a quarter would be red RR , and a quarter would be white rr as you can see in the Punnett square below.

Cows with the genotype BB are completely black, those with the genotype WW are completely white, and when they are crossed, cows with the genotype BW have black and white spots across their body. When doing a cross that follows codominance inheritance patterns, all capital letters are usually used to represent the alleles to show no allele is dominant over the other.

Below is a Punnett square showing what happens when you cross a pure black cow BB with a black and white spotted cow BW. From the Punnett square, you can see that half of the offspring will be pure black, and the other half will have black and white spots. Incomplete dominance is when the phenotypes of the two parents blend together to create a new phenotype for their offspring. An example is a white flower and a red flower producing pink flowers.