Pleiotropy is a phenomenon that takes place when a single gene affects many properties in living organisms A gene mutation can result in pleiotropy. Pleiotropy can be seen in the human genetic disorder Marfan syndrome, which affects the connective tissues. This illness commonly affects the eyes, heart, blood vessels, and bones. Pleiotropy is caused by a Marfan Syndrome-causing mutation in a human gene.
EFFECT OF GENES ON HUMAN TRAITS
The physical traits of a person, such as body structure, height, colour, physique, and height, are referred to as phenotypes. A single gene trait is a trait that is regulated or controlled by a single gene It may be difficult to determine the presence of pleiotropic features until the gene is subjected to mutation.
Mutations are changes in DNA sequences that happen about one another. The most common type of gene mutation is a point mutation, which is further broken down into silent mutations, nonsense mutations, and missense mutations.
The character of the qualities is generally determined by the two alleles, which are the variation form of a gene, according to various literature. The formation of proteins that derive the process of phenotypic characteristic development is dictated by the combinations of diverse alleles, whilst the DNA sequence of the gene is altered by the mutation that occurs in the gene. As a result, changes in the sequencing of gene segments cause proteins to stop working. As a result, the progressions in the mutation will affect all possible characteristics that are related to a single attribute in the pleiotropy process.
GENE PLEIOTROPY
Pleiotropy was first proposed in biology by Gregor Mendel, a well-known geneticist well recognised for his groundbreaking work on pea plants. He observed, that vibrantly coloured flowers and leaf axils are always visible on plants with coloured seed coats, An axis is the component of the plant that connects the stems to the rest of the plant.
He noticed that although the seed coats were colourless in nature and had no colouring in their axis, the pea plants, which were the focus of the study, invariably had white blossoms. After reviewing his findings, it was determined that the colour of the plant’s axil and the seat coat are the most crucial criteria in determining whether the plant would produce white or purple flowers. Today, the phenomenon of Pleitropy is now credited with identical discoveries. in which a single gene contributes to several phenotypic traits.
Pleiotropy may be caused by several different methods, including development pleiotropy, gene pleiotropy, and selectional pleiotropy.
Gene pleiotropy, also known as molecular gene pleiotropy, is a kind of pleiotropy that focuses on the functionality of a single gene. The number of features and biochemical components impacted by a gene determines the function of a characteristic in general. The biochemical parameters include the number of enzyme reactions facilitated by the gene’s protein products.
The primary emphasis in the development of pleiotropy is mutations and their relative effect on several traits. Single-gene changes have been proven to have a larger impact on a variety of other possible traits. Furthermore, disorders involving mutational pleiotropy are defined by defects in several organs that disrupt the proper functioning of multiple bodily systems
Selectional pleiotropy, which focuses on the effect of gene mutations on the number of unique fitness components, is the last step that generates pleiotropy. The mechanism by which an organism passes its genes from one generation to the next through sexual reproduction is typically governed by the fitness of the organism.
EXAMPLES OF GENE PLEIOTROPY
Deafness and Pigmentation in Cats
Around 40% of cats with white coats and blue eyes have been proven to be deaf, according to reports. Although this information is remarkable because we have most likely never paid attention to these cats throughout our lives. It was found early on in the research that white cats with one blue eye and one yellow eye were blind in one eye, which was generally the blue eye, but it was afterwards shown that this condition of blindness does not apply equally to all cats breeds.
Sickle Cell Disease
The most prevalent kind of pleiotropy that affects people is sickle cell disease, which is caused by a disorder that causes abnormally shaped red blood cells, whereas normal red blood cells have a biconcave, disc-like shape and contain high amounts of haemoglobin.
Red blood cells in the blood are largely responsible for binding tissues and carrying oxygen to all available cells. Sickle cells are most commonly caused by a mutation in the beta-globin gene. As a result, irregularly shaped blood cells cluster together, producing a block in the veins and eventually blocking blood flow in the veins. This obstruction causes a slew of health issues as well as harm to essential human organs including the heart, brain, and lungs.
CONCLUSION
The property that shows that multiple genes have many phenotypic effects is called pleiotropy. Pleiotropy can often arise through some the very overlapping but distinct mechanisms such as development pleiotropy, gene pleiotropy, and selectional pleiotropy. In gene pleiotropy, the major focus is on the functionality of the particular gene while in development and selectional pleiotropy the focuses are on the mutations and their relative impact on the many traits and the effect of gene mutations on the number of separate fitness components respectively.