There is a lot of confusion while delving into the intense world of genes and alleles. Each of them is a fundamental concept in the study of hereditary. Gene and allele are two different aspects of our genetic makeup. This article will help you to understand the concept and know the difference between genes and alleles.
Difference Between Gene And Allele
What Is A Gene?
Your gene is a segment of your DNA that has the instructions for building a specific type of protein. This in turn plays a vital role in determining your characteristics. Genes are the basic heredity units located on chromosomes in the cell nucleus. Each gene occupies a specific location (locus) on a chromosome.
For example, there is a gene responsible for determining eye color. This gene contains the instructions for producing the pigments that give our eyes their color. Some of the wide array of functions that genes are responsible for are as follows –
- Physical characteristics – height and skin color
- Metabolic processes
What Is An Allele?
An allele is an alternative version of a gene. Since genes come in pairs, mostly one from each biological parent, the alleles can be identical or different. These different versions of a gene are what create genetic diversity within a population. For instance, the gene for eye color has multiple alleles, which is why people have blue, green, brown, or hazel eyes. Alleles can be of two types namely
- Dominant
- Recessive
A dominant allele will express its trait even if only one copy is present, while a recessive allele only expresses its trait if both copies are present. For example, if the allele for blue eyes is dominant then the person will have blue eyes even if the recessive for the brown eyes.
Difference Between a Gene and an Allele
The difference between a gene and an allele is often compared to the difference between a general concept and its specific instances. A gene is a section of DNA that governs a certain trait, while an allele is a specific version of that gene. In other words, while a gene is a unit of heredity, an allele is a variant of that gene.
To elaborate, consider the gene that determines flower color in certain plants. Your gene can exist in different forms, or alleles, such as the allele for purple flowers (P) and the allele for white flowers (p). The gene itself determines the flower color, but the specific allele present will determine whether the flower is purple or white.
What Is The Difference Between Gene Allele And Trait
Traits are the observable features produced by the interaction of genes and their alleles. A trait can be influenced by a single gene, as in Mendel’s pea plants, or by multiple genes interacting together, as is often the case in humans.
When a trait is determined by a single gene, it is called a Mendelian trait. In such cases, the difference between genes and alleles becomes very clear. In one of the experiments called Mendal’s experiment, the flower had two alleles, one for purple and one for white flower. The offspring’s color will be determined by the combination of these two flowers.
Difference Between Gene and Allele: Class 12 Perspective
From a Class 12 biology perspective, understanding the difference between a gene and an allele is crucial for mastering genetics. Here’s a concise breakdown:
Gene
A gene is a segment of DNA that contains coding for a specific protein. It represents the basic unit of heredity and can influence one or multiple traits.
Allele
A variant form of a gene. For example, in human blood types, the ABO gene determines blood type, but the alleles (A, B, and O) determine the specific blood group (A, B, AB, or O).
Genetic testing has become a foundation in modern medicine, allowing the following things
- Prediction of disease risk
- Personalized treatment plans
Central to genetic testing are the concepts of genes and alleles, which together form the basis of your genetic makeup. Understanding how genes and alleles relate to genetic testing is important for comprehending how these tests work and what they can reveal about your health.
The Relationship Between Genes, Alleles, And Genetic Testing
Genetic testing will help your DNA to analyze and identify changes or variations in genes and alleles. It will also help you to indicate certain diseases and their risks.
Detection Of Mutation
The areas that can lead to fatal diseases in your body in the future can be identified with the help of genetic testing. This variation can occur in any allele of the gene. Let us take an example for your better understanding, in the case of cystic fibrosis, genetic testing looks for mutations in the CFTR gene. Individuals with specific mutations in both alleles of this gene will develop the condition.
Identifying Carrier Status
One of the main benefits of genetic testing is that it helps to determine your recessive allele genes that could be passed to their kids. For example, individuals carrying one normal allele and one mutated allele for the gene responsible for sickle cell anemia do not exhibit symptoms but can pass the mutated allele to their children.
Assessing Disease Risk
Genetic testing can assess the risk of developing certain diseases based on the presence of specific alleles. Let us take the example of, the BRCA1 and BRCA2 genes have alleles that, when mutated, significantly increase the risk of breast and ovarian cancers. By identifying these alleles, individuals can take all the precautionary measures or early treatment.
Pharmacogenomics
Pharmacogenomics is the study of how genes and their alleles affect an individual’s response to drugs. Genetic testing in pharmacogenomics can identify which alleles a person has for genes that influence drug metabolism, helping to tailor medication plans for more effective treatment with fewer side effects.
Conclusion
Creating a difference between DNA through the understanding of genes and alleles is fundamental in the study of genetics. While on one hand genes represent the instructions for building and maintaining your body, on the other hand alleles are the variations of these instructions that contribute to our unique traits. By understanding the difference between genes and alleles, we can better appreciate the complexity of heredity and the variety of life.