21 Allele Facts For Kids: Learn How Alleles Interact And Their Functions

Sakshi Thakur
Oct 05, 2022 By Sakshi Thakur
Originally Published on Jan 31, 2022
Edited by Rhea Nischal
Fact-checked by Pratiti Nath
Genetics is a very interesting subject. Learn intriguing allele facts here at Kidadl!
Age: 3-18
Read time: 5.4 Min

Alleles are different variants of a gene.

Alleles are classified as dominant or recessive alleles based on their related characteristics. Because human cells contain two copies of each chromosome, each gene has two versions.

Alleles are the various variants of a gene. Here are a few interesting facts about the Alleles that play a major role in DNA studies. These facts shall bring in a deeper insight into your understanding of genetics. All living beings possess the alleles that determine characteristics for all living beings.

  • Alleles may be dominant or recessive alleles. Dominant alleles have an effect even if the person just has one allele (also called heterozygous). This shows the absence of recessive genes.
  • Codominance occurs when both alleles are dominant. The resultant trait is the result of both alleles being expressed equally. The blood group AB is one example of this since it results from the codominance of the A and B dominant alleles. The blood group is always written in capital letters.
  • Recessive alleles have an effect only if the individual has two copies of the allele (also known as being homozygous). For example, because the gene for blue eyes is recessive, you must have two copies of the 'blue eye' allele to have blue eyes. This is true for plants as well, like in white flowers, where the trait is like in humans. The dominant allele rules the trait to be followed.
  • The total number of genes encoded on a person's 46 chromosomes is referred to as their genotype. However, not all gene variants will be expressed. There can be incomplete dominance as an alternative form of traits. They can determine the inheritance of blood type, genotype, and so on depending on the mutation and the locus of the chromosome.
  • You could have one gene for brown eyes and another for blue eyes, but you won't have one blue and one brown eye. These are traits inherited from parents in humans and all living organisms.

What are alleles?

Alleles are gene copies that impact inherited traits. Each individual receives at least two alleles for each gene, one from each parent. Allelomorphs is another name for them.

  • Eye color is a wonderful illustration of how alleles are manifested; whether we have blue or brown eyes is determined by the alleles passed down from our parents. Alleles are considered a crucial element of the blueprint for all living organisms since they help establish what our bodies appear like and how they're built.
  • An allele is a variant of a gene found at a specific location (locus) on a chromosome. It is the coding DNA at that location.
  • Plants and animals often contain two sets of chromosomes, one from each parent. These creatures are known as diploids. Because such creatures have two sets of chromosomes, each gene locus has two alleles.

Types Of Alleles

Individuals do not exhibit the traits expressed by each matched pair of genes. Instead, the genes that are expressed produce a phenotype, which is how genes manifest themselves in observable qualities.

  • Every person has two copies, also known as alleles, of a single gene. Homozygotes are people who have the same alleles. When they vary, they are referred to as heterozygotes.
  • Blue eyes, for example, are coded for by homozygotes. Your eyes will be blue if you have two blue eye alleles. However, if you have one gene for blue eyes and another for brown eyes, the dominant allele will determine your eye color.
  • When present, a dominant allele always defines the phenotype. A recessive allele, on the other hand, is one that is not expressed when its matched allele is dominant.
  • When it comes to eye color, the brown eye allele outnumbers the blue eye allele. This means that a kid who inherits a blue allele from their mother and a brown allele from their father will have brown eyes. A child with two blue alleles, on the other hand, will have the blue eye phenotype.
DNA can decide what we shall look like. Learn allele facts that determine your characteristics here!

Functions Of Alleles

Alleles, together with DNA and genes, play a significant part in establishing our inheritance.

  • Deoxyribonucleic acid (DNA) is the genetic material passed down from one generation to the next.
  • Your DNA is divided into little pieces known as genes. Genes function as coded instructions that determine how our bodies are constructed and impact our appearance.
  • An allele is the variant of each gene that a parent passes on to their offspring. Alleles are found on chromosomes, the structures that house our genes. Alleles affect the way our cells function in our bodies, influencing features and characteristics such as skin pigmentation, hair color, eye color, height, and blood type.

How do Alleles work?

The features we acquire from our parents are determined by how the alleles interact with one another. The particular order in which alleles are put together is known as an inheritance pattern, and it accounts for all of the variances in an organism's genotype.

  • Because alleles include at least two sets of instructions for each gene, the body must determine which character people inherit. Consider the hue of your eyes. The two alleles handed down from parent to kid determine a person's eye color. Different versions result in brown, blue, green, or hazel eyes, though the latter two are more distinctive than brown or blue eyes.
  • When both parents contribute identical alleles for the eye color gene, the child is said to be homozygous. That is, the instructions provided by the alleles will be the same, resulting in the appearance of eye color. Multiple genes are available for selection that can lead to genetic diseases.
  • If both parents contribute different alleles to a gene, the child is said to be heterozygous, which means the instructions won't match and the body will have to follow the stronger (or dominant allele). Hetero denotes unique.
  • This is when things may get a bit complicated. Alleles can be either dominant or recessive. Even if only one copy exists, dominant alleles express a characteristic. Recessive alleles can only be expressed if two alleles exist, one from each parent. You've undoubtedly worked out by now that the dominant gene takes precedence over the recessive gene.
  • New alleles emerge in populations as a result of genetic mutations, and natural selection can also play a role in favoring some alleles over others.
  • In fact, some scientists believe that alleles are so important to human history that they define evolution as a change in alleles.

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Written by Sakshi Thakur

Bachelor of Science

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Sakshi ThakurBachelor of Science

Sakshi is a skilled content writer with extensive experience in the education industry. With a keen eye for detail and a passion for helping others, she has developed a reputation for excellence in academic content writing. She has worked with esteemed professionals such as Mr. Kapil Raj, a professor of History of Science at the École des Hautes Études en Sciences Sociales in Paris, further enhancing her knowledge and expertise. Sakshi is well-versed in the latest developments in e-learning and has a deep understanding of how to engage students and make learning fun and accessible. In her spare time, she indulges in her creative passions, including painting, embroidery, and listening to soft music. She also enjoys exploring new cultures and traveling, which helps her broaden her perspectives and inspire her writing. She holds a Bachelor's degree in Science from Panjab University.

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Fact-checked by Pratiti Nath

Bachelor of Science specializing in Microbiology, Masters of Science specializing in Biotechnology

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Pratiti NathBachelor of Science specializing in Microbiology, Masters of Science specializing in Biotechnology

A Master's in Biotechnology from Presidency University and a Bachelor's in Microbiology from Calcutta University. Pratiti holds expertise in writing science and healthcare articles, and their inputs and feedback help writers create insightful content. They have interests in heritage, history, and climate change issues and have written articles for various websites across multiple subjects. Their experience also includes working with eco-friendly startups and climate-related NGOs.

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