Dominant and recessive are the two types of genes. The main difference between dominant and recessive is, dominant gene is expresses completely in the phenotype while recessive gene is not completely expresses in the phenotype. Recessive gene cannot be fully expressed in the presence of a dominant gene but when it is alone, it is expressed fully.
What is Dominant?
Dominant gene, trait, factor or even allele is capable of expressive itself completely in a phenotype, even in the presence of recessive gene. It is able to express itself, irrespective of the presence of recessive gene. It does not require similar allele to produce its effect on the phenotype. Moreover, dominant factor is capable of forming a complete polypeptide or forming a complete enzyme for expressing its effects. For instance, red color of a flower or tall height of a person. A person or even a plant is said to acquire the character which is dominant in nature rather than the recessive one. Dominant alleles are useful but in some cases like in achondroplasia, which is a form of dwarfism, dominant mutations occur in some genes which results this disease. Therefore some alleles can result lethal in certain homozygous conditions.
What is Recessive?
Recessive genes are not fully expressed in a phenotype unlike dominant genes. In a nutshell, they are not able to produce their complete effects in the presence of a dominant gene. If a similar allele is present, then is when it could produce its phenotypic effects only. Defective, incomplete polypeptide or enzyme is the possible production of a recessive gene. So that the expression produced by the gene consists of absence of effect of the dominant gene. In many cases, recessive mutations could be lethal or can produce loss of function. For instance, the gene of albinism is recessive because the body needs only one gene of melanin to provide pigmentation to skin, hair, eyes or nails. If there is a mutation in that one gene then albinism occurs.
Key Differences between Dominant and Recessive
- Dominant gene expressed completely in a phenotype while recessive is not.
- Dominant genes that cause serious diseases are less common than the recessive genes.
- Dominant genes can be eliminated in the first generation while recessive genes are not selected out unless the person has two copies.
- A dominant gene is stronger than a recessive gene.
- Dominant genes are more likely to pass on to the off spring rather than recessive genes.