Whether or not a trait is common has to do with how many copies of that gene version (or allele) are in the population. It has little or nothing to do with whether the trait is dominant or recessive. … Instead, it is because there are mostly brown alleles of OCA2 in the African population.
Are dominant alleles more common?
A widespread misconception is that traits due to dominant alleles are the most common in the population. While this is sometimes true, it is not always the case. For example, the allele for Huntington’s Disease is dominant, while the allele for not developing this disorder is recessive.
Why is recessive more common than dominant?
Recessive disease mutations are much more common than those that are harmful even in a single copy, because such “dominant” mutations are more easily eliminated by natural selection.
How can dominant traits be uncommon?
Rare Dominant Genes
Some dominant genes are rare, meaning that a small subset of humans have the dominant allele. The polydactyly trait — having extra fingers or toes — is one example of a rare inherited dominant gene trait.
Do dominant alleles become more common over time?
In natural selection, having a certain trait makes an individual more reproductively successful than individuals lacking the trait. Thus, the allele that codes for the favored trait is passed on to more offspring, and becomes more common over time. The result: the frequency of the dominant allele goes up over time.
Is anyone dominant for every trait?
No organism has all dominant or all recessive genes. An organism may be pure in certain traits and hybrid others. Remember, that a dominant trait in one kind of organism may be a recessive trait in another organism. 1.
Is curly hair dominant or recessive?
Curly hair is considered a “dominant” gene trait. Straight hair is considered “recessive.” To put that in simple terms, that means that if one parent gives you two curly haired genes and the other parent gives you a pair of straight-haired genes, you’ll be born with curly hair.