What Is the Difference Between a Gene and an Allele with Definitions and Examples
Genes are the most basic and functional unit of heredity. In other words, it means that genes make up our DNA structure and are responsible for all the genetic traits that we have. Every human being has two copies of each gene, i.e one from each parent. Usually, these genes are the same for all individuals, but less than 1% of the total difference between individuals and these are responsible for the variations and uniqueness of each individual. These changes or alterations in the genes are called an allele.
Gene vs Allele
A gene essentially is part of the DNA structure and it decides the genetic traits of all individuals. Alleles determine a single characteristic and different variations of the same gene.
The difference between gene and allele are as mentioned below -
Difference Between Gene and Allele
Functions of Genes and Alleles
Genes play a vital role as they are responsible for building traits in an organism. They act as instructions for protein synthesis. There are two copies of genes inherited from each parent. These are known as alleles that play an important role in shaping the features of the individuals.
It can be concluded that everyone takes over a pair of genes from their parents, and these genes are identical to each other. Now, each individual is obvious and these changes are the result of alleles.
Chromosomes
Chromosomes are structures which are coiled and made up of DNA and proteins. Chromosomes have their coded genetic instructions with which they make proteins. These instructions are organized into units called genes. Most genes ought to follow the instructions for a single protein. There can be an infinite number of genes on a single chromosome.
Human Genes
Humans have an estimated 20,000 to 22,000 genes. This may sound like a lot, but it really isn’t. Many other simpler species have almost as many genes as the humans have. However, splicing and other processes are used by humans to make multiple proteins from the instructions encoded in a single gene. Only about 25 percent of the nitrogen base pairs of DNA in human chromosomes make up genes and their regulatory elements. Out of this 25 percent, only two percent code for genes. The functions of many of the other base pairs are still unclear.
The majority of human genes have two or more possible versions, called alleles. Differences in alleles have a considerable genetic variation among people. In fact, most human genetic variation is the result of differences in individual DNA base pairs within alleles.
Benefits of referring to Vedantu for Biology- Gene vs Allele
Students have been learning the concept of genes since Grade 9. This topic falls under the subject matter of Biology for Class 10 and Class 12. In Class 10, students are briefly familiarized with the topic. However, in Grade 12, the topic is explained in detail.
While explaining the difference between the two terms, Experts at Vedantu always make sure to include a clear tabular representation for it.
Often, the students miss out on describing the difference in detail. On the website of Vedantu, you will clearly differentiate problems that can help you in avoiding vaguely researched and not studied points.
Vedantu makes sure to follow a certain order while explaining the topics. For instance, once the students have completed the thorough learning of the definitions and differences, experts then explain the functions of each.
In addition to explaining the functions, it is important that students mention the differences of the functions for these two. You can find the relevant points on the website.
Along with the explanations of genes and alleles, the topic of chromosomes is equally important. Without understanding the definition of chromosomes, the concept of genes would be incomplete and complex.
In conclusion, Experts have specifically added and explained the topic of Human genes. It covers all the details along with some interesting facts to make the learning process earlier.
In addition to the biological facts, Experts also give some statistically valid points related to genes and alleles. These points help in maintaining curiosity and make the learning process easier.
Followed by these, the website contains 'Frequently- asked questions’. Such questions are well-researched and tend to repeat often in the board exams.
If you encounter any such question for your exams, experts at Vedantu advise you to keep it to-the-point yet cover all the important definitions and functions of both the genes and alleles.
FAQs on Difference Between Gene and Allele in Genetics
1. What is the difference between a gene and an allele?
The main difference between a gene and an allele is that a gene is a segment of DNA that controls a trait, while an allele is a different version of that gene.
- A gene is a specific sequence of DNA that codes for a protein or functional RNA.
- An allele is an alternative form of the same gene found at the same locus on homologous chromosomes.
- For example, the gene for eye color may have a brown allele and a blue allele.
2. What is a gene in biology?
A gene is a unit of heredity made of DNA that carries instructions for making a specific protein or RNA molecule.
- Genes are located on chromosomes inside the nucleus.
- Each gene occupies a specific position called a locus.
- Genes determine traits such as height, blood group, and hair color.
3. What is an allele in genetics?
An allele is an alternative form of a gene that arises by mutation and is found at the same locus on homologous chromosomes.
- Organisms usually inherit two alleles for each gene—one from each parent.
- Alleles can be dominant, recessive, or show codominance.
- Different alleles produce variations in a trait, such as different blood groups in humans.
4. How are genes and alleles related to each other?
Genes and alleles are related because alleles are different versions of the same gene.
- A single gene controls a particular trait.
- Multiple alleles of that gene can exist in a population.
- Each individual carries two alleles for most genes—one on each homologous chromosome.
5. Can you give an example of a gene and its alleles?
A classic example of a gene and its alleles is the human ABO blood group gene.
- The ABO gene determines blood type.
- It has three main alleles: IA, IB, and i.
- Different combinations of these alleles result in blood groups A, B, AB, or O.
6. How many alleles can a gene have?
A gene can have two or more alleles in a population, but an individual typically carries only two alleles for that gene.
- In diploid organisms, each individual inherits one allele from each parent.
- At the population level, a gene may have multiple alleles due to mutations.
- For example, the ABO gene has three common alleles.
7. What is the function of a gene and an allele?
The function of a gene is to code for a functional product, while the function of an allele is to produce variation in how that gene’s trait is expressed.
- A gene provides instructions for synthesizing proteins through transcription and translation.
- An allele may alter the protein’s structure or amount, leading to different phenotypes.
- For example, different alleles of a pigment gene can result in varied skin or eye color.
8. Where are genes and alleles located in the cell?
Genes and their alleles are located at specific positions on chromosomes within the cell nucleus.
- Genes are segments of DNA found on chromosomes.
- Each gene occupies a fixed position called a locus.
- Alleles are different forms of the same gene located at the same locus on homologous chromosomes.
9. What is meant by dominant and recessive alleles?
A dominant allele expresses its trait even when only one copy is present, while a recessive allele expresses its trait only when two copies are present.
- In a heterozygous condition, the dominant allele masks the effect of the recessive allele.
- In a homozygous recessive condition, the recessive trait is expressed.
- This pattern was first described by Gregor Mendel in pea plants.
10. Why are alleles important for genetic variation?
Alleles are important because they create genetic variation within a population, which is essential for evolution and adaptation.
- Different alleles produce different versions of a trait.
- Variation allows natural selection to favor beneficial traits.
- Mutations generate new alleles over time.
