What Sets a Gene Apart From an Allele?
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 Gene vs Allele: Understanding the Core Differences
1. What is the fundamental difference between a gene and an allele?
The fundamental difference lies in their relationship: a gene is a specific segment of DNA that codes for a particular trait (like eye colour), while an allele is a specific version or variation of that gene (like the allele for blue eyes or the allele for brown eyes). In simple terms, a gene is the instruction, and alleles are the different forms that instruction can take.
2. Can you give a clear example to explain the difference between a gene and its alleles?
Certainly. Consider the gene responsible for blood type in humans. This single gene has three different versions, or alleles: IA (for A-type blood), IB (for B-type blood), and i (for O-type blood). Every individual inherits two of these alleles, one from each parent, which determines their specific blood type.
3. How are genes, alleles, and chromosomes related to each other?
These terms describe the organisation of genetic material. Chromosomes are large, thread-like structures made of tightly coiled DNA. A gene is a specific section on a chromosome that carries the code for a protein or functional RNA. Alleles are the different versions of the same gene, found at the exact same location (locus) on a pair of homologous chromosomes.
4. What is the main function of genes and alleles in an organism?
The main function of a gene is to act as a blueprint, providing the instructions for building proteins. These proteins then carry out various tasks, determining an organism's traits. The function of alleles is to introduce variation into these traits. The specific combination of alleles inherited by an organism dictates the final observable characteristic, or phenotype.
5. How do different alleles for the same gene arise in a population?
Different alleles primarily arise through mutation. A mutation is a random, permanent change in the nucleotide sequence of a gene's DNA. This alteration can create a new version of the gene, which is a new allele. While some mutations can be harmful, many are neutral or may even introduce a beneficial trait, contributing to genetic diversity within a population.
6. How do dominant and recessive alleles interact to determine an organism's traits?
When an organism inherits two different alleles (a heterozygous state), their interaction determines the trait.
- A dominant allele is one that expresses its trait even if only one copy is present.
- A recessive allele is one that is only expressed when two copies are present (a homozygous state).
7. Is a 'dominant' allele always better or more common than a 'recessive' allele?
No, this is a common misconception. 'Dominant' simply refers to which allele is expressed in a heterozygous individual; it does not imply that the allele is superior, stronger, or more frequent in a population. For instance, the allele for Huntington's disease is dominant, but it is very rare and certainly not 'better'. Conversely, the allele for Type O blood is recessive but is the most common blood type in many populations.
8. What is the importance of having two alleles for each gene in diploid organisms like humans?
Having two alleles for each gene, one inherited from each parent, is crucial for several reasons. Firstly, it creates genetic diversity, which is the foundation for evolution and adaptation. Secondly, it provides a 'backup' copy. If one allele is mutated and non-functional (often a recessive allele), the normal dominant allele can often produce enough of the required protein to maintain a healthy phenotype, masking the effect of the faulty allele.
