Biology

Difference between dominant gene and recessive gene

Main difference

The main difference between the dominant gene and the recessive gene is that the dominant gene is the one that masks the expression of the other trait, while the recessive gene is the one that hides the dominant gene.

Dominant gene vs. recessive gene

A dominant gene is a type of gene that dominates the inheritance pattern and masks the other, on the other hand, a recessive gene is one that does not show its trait in the inheritance pattern and is hidden by the dominant one. A dominant gene is a stronger gene, while the recessive gene is a week gene. The dominant gene is always expressed in uppercase letters like A, F, V, while the recessive gene is always denoted with lowercase letters like a, f, and v. The dominant gene is shown in inheritance when one of the two genes is dominant but in the case of a recessive gene both genes of a trait must be recessive.

Comparative chart

Dominant gene Recessive gene
The dominant gene ultimately determines the expression of a trait. Receptor genes are those that are least likely to be expressed
Documented
A dominant gene is written in capital letters. A recessive gene is written in lowercase
Gene type
A dominant gene is a strong gene A recessive gene is a week gene
Condition
It always shows if it is present It only shows if both are present
Examples
Brown eye trait, blood group A and B Blue-eyed trait, blood type O

What is the dominant gene?

The terms dominant gene describe the inheritance patterns of certain traits. A dominant allele produces a dominant phenotype in individuals who have one copy of the allele, which can come from only one parent. Dominant alleles are those that show their effect even if the individual has only one copy of the allele also known as heterozygous. For example, the gene for red eyes is dominant. Therefore, you only need one copy of the red-eye allele to have red eyes, whereas with two copies you will still have them. If both alleles are dominant, it is known as codominance. The resulting characteristic is due to the fact that both alleles are expressed equally. An example of this is blood group AB, which is the result of the codominance of the dominant alleles A and B.

Examples
  • Dark hair is dominant over red and blonde hair.
  • Curly hair predominates over straight hair.
  • The ability of an individual to roll the tongue is dominant over the inability to do so.
  • Astigmatism dominates common vision.
  • The presence of webbed fingers is a dominant type trait.
  • The development of six fingers instead of five is controlled by dominant genes.
  • When having a widow’s peak, a V-shaped hairline is dominant over the straight hairline.
  • Freckles, a cleft chin, and dimples are examples of a dominant trait.
  • Having almond-shaped eyes is a dominant trait, while having round eyes is a trait controlled by recessive alleles.

What is the recessive gene?

A recessive gene is a gene that can be masked by the dominant gene. The terms recessive gene describe the inheritance patterns of certain traits. To produce a recessive phenotype, the individual must have two copies, one from each parent. Recessive alleles show their effect on inheritance if the individual has two copies of the allele also known as homozygous. For example, the blue eye gene is recessive, therefore, to have blue eyes it is necessary to have two copies of the blue eye allele. Some disorders are autosomal recessive, such as cystic fibrosis, Tay-Sachs disease, and sickle cell anemia. A recessive gene is always expressed in lowercase letters such as a, z, and h. A recessive gene trait comes in inheritance when both genes are recessive.

Examples

  • Having a straight hairline is recessive.
  • Individuals with cleft chin recessive alleles.
  • Having round eyes (unlike almond-shaped ones) is recessive.
  • Inability to roll the tongue.
  • Attached (as opposed to free) earlobes are also a recessive trait.
  • Having blue eyes is recessive to brown eyes.
  • Having round eyes is a trait controlled by recessive alleles.
Key differences
  1. The dominant gene produces the dominant phenotype while a recessive gene does not provide a dominant phenotype.
  2. A dominant gene is stronger than a recessive gene, since it masks the effect of the recessive gene.
  3. The dominant genetic trait is expressed in capital letters like H, V and L on the other side, the recessive genetic trait is shown in lowercase letters like h, v and l.
  4. The dominant gene is fully expressed in the phenotype, while the recessive gene is not fully expressed in the phenotype.

Final Thought

The conclusion of this article is that the dominant gene is the one that masks the effect of the other gene, on the other hand, the receptor gene is the one whose character is hidden by the other dominant gene.

Leave a Reply

Your email address will not be published.

CAPTCHA


Back to top button