Codominance vs Incomplete Dominance
Learning about how physical traits of plants and animals develop is one of the reasons why genetics is such an interesting subject to study.
Identifying what sets codominance apart from incomplete dominance can be made easier if we break it all down into simple and easy to grasp parts. First, we’ll discuss how physical features like red hair, blue eyes, or freckles are passed on from parents to their offspring. We often hear people say ‘that girl has good genes’ or ‘he got his singing voice from good genes’ but most of us don’t understand the process behind it or how it happens.
Genes contain alleles which are also called DNA sequences. They contain information about traits that can be passed on from parents to their progeny or children. There are two types of alleles inside a gene; dominant and recessive. Dominant alleles are the most likely traits that will show up in the offspring while recessive ones will occur in the succeeding generations.
To illustrate this we’ll use dogs. If a spotted dog is mated with a plain colored one, they will pass on genes that contain alleles for both spots and plain color. Now if the dominant allele happens to be spots, the resulting offspring will most likely to show this trait – i.e. be a pup with spots. But since dogs rarely give birth to a single puppy, the plain color allele will still show up in one or two puppies, the spotted ones will outnumber them however. This phenomenon is referred to in genetics as dominance.
Now that we know all about dominance and how it affects formation and passing of traits, we can move on to its two types ‘“ incomplete dominance and codominance. From the outset they can be very confusing because both processes involve the presence of alleles that are neither dominant nor recessive. However, the similarities end there as both have different results that are reflected in the appearance of the traits they carry.
In order to show just how different one is from the other, we need to use an example. Incomplete dominance is usually exhibited in humans and other animals. When a father has curly hair and the mother’s is straight it could manifest as a combination of both alleles for hair which is wavy. In other words, both traits can exist as one in an offspring.
Codominance on the other hand is common in plant species. A yellow flower with red leaves can be combined with another flower of the same color but with green leaves. Instead of combining these traits to form another one, both of them can exist together which means the resulting flower will have both green and red leaves. This just shows that while both types of dominance can occur with neither alleles being dominant or recessive the results are very different from each other.
Summary:
1.Incomplete dominance and codominance show both alleles from either genes as neither recessive nor dominant.
2.Incomplete dominance results in a mixture of alleles that comes out as one unique trait while codominance results in both attributes being present at the same time.