What is the Difference Between Genotype and Phenotype? And do you have a clear example of that?

Answer

Dear Anthony,

The genotype refers to the hereditary information stored in the DNA in the form of genes. All properties and characteristics of an organism are initially determined by its genotype. The phenotype refers to how the hereditary information is expressed and visible. Thus, the phenotype is determined by the genotype. Since environmental factors can play a role in the way in which the hereditary information is expressed, organisms with the same genotype (eg identical twins) do not necessarily have the same phenotype. Moreover, many traits are determined by several genes, so that it is not always easy to determine which genotype is responsible for a specific phenotype.

The hereditary information is always present in diploid organisms such as humans: there are two copies for each gene. One copy comes from the mother, the other from the father. The information contained in these gene copies need not be identical. If one gene has the upper hand, we call it dominant, if both copies together determine the trait, we call this intermediate. A classic example is the color of the eyes. For example, the gene carrying the information for this can be brown (B) or blue (b). Brown is dominant. If your genotype is BB or Bb, you have brown eyes; if it is bb, you have blue eyes. Other characteristics such as how tall you grow are not only determined by your genotype, but also by environmental factors: nutrition, hygiene,… In other words, don’t blame your genes (and therefore your parents) for everything!

If you want to know more, you can check out the web link on Mendel’s Laws.

regards