Genotype: Function, Tasks, Role & Diseases

The genotype is the totality of all genes in the cell nucleus. Based on their arrangement, processes in the body are initiated and body compartments such as organs and external characteristics are formed. Moreover, the causes of many diseases are hidden in the genotype.

What is the genotype?

Genotype genes are located on the 46 chromosomes of the human cell. The genotype includes the entire set of chromosomes that the individual inherited from his or her parents. Genotype genes are located on the 46 chromosomes of the human cell. The genotype is counted as the entire set of chromosomes that the individual has inherited from its parents. Previously, during meiosis, the duplicate chromosome sets of the parents were halved. For this reason, the zygote, the developing life, again inherits a duplicate set of chromosomes, since one bisected chromosome is passed on from each parent generation. On the one hand, genes are responsible for the expression of a phenotype, which is expressed in features of physical appearance as well as in the internal structure of the body. On the other hand, they carry the information for many different processes in the human organism. The genotype is nothing less than a microscopic imprint of the living being. For this reason, it is also called a biological fingerprint.

Function and task

Genes determine the biological process in human and animal organisms. They are based on specific base chains arranged in a double helix structure. The bases building the genes include adenine and thymine, and guanine and cytosine. On the respective opposite DNA strands that contain the genes and together support the double helix, adenine complements thymine and guanine docks with cytosine. Humans are eukaryotic organisms. This means that its genetic material is enclosed in and protected by a nucleus. In prokaryotic organisms, the DNA strands are in the cytoplasm and float through the organism. All metabolic processes begin at the genetic level. Within the framework of its genetic predisposition, the body is able to produce metabolic products and react to external influences. Messenger substances in the human organism read the genetic material like a data carrier and use this data to initiate processes such as protein production or the formation of individual enzymes. In addition, the genetic material determines certain characteristics of the body such as size, appearance or the functionality of organs. These characteristics are formed during ontogenesis and body growth due to genetic predisposition. The genes are recombined beforehand during sexual intercourse and subsequent fertilization of the egg, so that the zygote receives a unique gene complex. Recombination of genotypes of the parent generation ensures high variability and flexibility of the population. Thanks to such mechanisms as recombination and mutation, a random change in the genome, evolutionary advantages can arise. In this way, the gene pool of a population is updated, so to speak. This favors the adaptability of organisms to constantly changing environmental influences. Species with a high adaptability have an increased chance in the struggle for survival. Therefore, genotype composition has been shown to be a fundamental condition for the persistence of an individual and its success in reproduction. However, effective transformations of the gene pool of a species take place in periods of time that a human life cannot cover. Therefore, humans today can determine large-scale mutations only retrospectively. In epigenetics, however, small-scale gene changes can also be detected in the course of a human lifetime. It is undeniable that the human success story over the last millennia is due to high adaptability and serendipitous mutations of genetic material.

Diseases and ailments

Accordingly, genetic predispositions determine many aspects of human life from the outset. While some people have exceptionally good predispositions, others suffer from defective or inadequate predispositions in their genetic material. In today’s research, it is believed that a large proportion of diseases originate in the genetic material. Allergies and intolerances, for example, are highly hereditary. A weak immune system can also be traced back to genetic causes.People with a high susceptibility to lung diseases or colds often have relatives with the same susceptibility. In many families, disease patterns occur more frequently. For example, those who have several relatives who have or have had heart disease also show an increased risk for potential heart disease. The same is true for the many different types of diseases that belong to the group of carcinogenic diseases. Cancer risk appears to be transmitted from parent to child. A young woman who has many cases of breast cancer in the family is at a significantly higher risk of also developing it than a person with no cases of cancer in the family. In the case of other diseases, the so-called hereditary diseases, not only a risk is inherited. Since the diseases are coded by specific sections on the chromosomes, they can be passed on in their entirety to the generation of children. The best-known hereditary diseases include Wilson’s disease, albinism and cystic fibrosis. Trisomy 21, also known as Down syndrome, is a special case among hereditary diseases. Here the zygote receives three instead of the usual two chromosomes of the 21st chromosome pair. The unveiling of the genotype and the recording of its data sequence has brought about an advance in diagnostics. Nowadays, by means of prenatal diagnostics it is possible to calculate the risk of disease of an embryo for many pathological phenomena. This leads more and more often to the fact that prophylactic measures can be taken. Unfortunately, the discovery of risk for many diseases does not yet coincide with strategies to control them. Nevertheless, knowledge of the genotype helps to localize responsible defective areas and thus to explore the origins of the disease.