A gene may be defined as a hereditary unit comprising a series of DNA (deoxyribonucleic acid) that is found at a particular site on a chromosome and influences a specific attribute in a living organism. Genes usually go through a mutation process with the alteration of their DNA sequence. In other words, a gene is usually an expanse of DNA that programs or codes for a form of protein or for RNA (ribonucleic acid) sequence which has a specific role in the organism. In effect, the genes specify all protein as well as functional RNA sequences, hence, all living organisms depend on genes.
Genes function as subunits of DNA and possess all information to develop as well as sustain the cells of an organism and help to disseminate the genetic characteristics to the offspring. Precisely speaking, a gene may be called a unit of a living organism. All living organisms comprise of and depend on genes. Simply speaking, genes are a collection of commands that determine several aspects of an organism - its appearance, form, the manner in which it continues to exist and the manner it conducts itself in its environment. The genes are found in long stretches of DNA known as chromosomes. Humans have a total of 46 chromosomes found in 23 pairs.
As aforementioned, the genes possess the information to develop as well as sustain the cells of an organism and pass on the genetic attributes of the organism to its offspring. In fact, a gene only forms an element of a DNA molecule that encodes for a specific attribute of an organism. A gene offers directives regarding the process to produce a polypeptide (a sequence of amino acids connected by peptide bonds). For instance, a solitary gene is able to code for producing tyrosinase (an enzyme or protein that is utilized in the amalgamation of melanin - a pigment that imparts the dark complexion to the skin and fur).
According to the conventional definition, a gene is copied into mRNA (messenger RNA) that is subsequently transformed into a protein producing the needed impact in the cell of an organism. In other words, mRNA is copied out from a gene and subsequently translated by ribosome (any of abundant minuscule particles in the cytoplasm of cells) with the intention of manufacturing a protein. At the same time, there are some genes that may enclose instructions for producing RNA that do not translate into protein like the rRNA, tRNA, siRNA and miRNA.
In order to carry out their work, the genes require something other than the mere code for any product. There are several regulatory sections (managers) in every gene that are imperative for its regulation. The first such regulator or regulating section is known as a 'promoter' that regulates things like activating or deactivating a gene. The promoter is effective in controlling the precise cells that the gene will function in, the time when the gene will operate as well as the duration and the extent to which it will work.
The second regulator or regulating section is found at the end of the gene. This regulator is known as the 'stop regulator' and is responsible for controlling the time when the gene will cease to work and also the period for which the gene's product would endure or last. The code of the protein product lies between these two regulator sections of the gene.
It may be noted that every living organism possesses its individual regulators. Therefore, a complete gene from one living organism will not work by design in case it is placed in another organism. In order to enable a gene function in a separate organism, it is generally essential to insert the regulator sections appropriate for an organism in conjunction with the gene.
It is important to note that the genes of an individual or any organism actually determine almost everything about the person or the organism. The genes are actually programmed to perform several functions and below is a list of a few of the fundamental attributes and characteristic that the genes are planned to perform.
Your genes determine:
Presently, several scientists are completely engaged in researching and examining genes. They are trying to find what the proteins produced by each gene precisely do inside the body. They are also trying to ascertain the exact diseases that are caused by genes that do not function properly. According to researchers, genes that might have modified in some way or the other - such genes are called altered or mutated genes - may be responsible to some extent for certain ailments, such as cancer, lung problems and other health conditions.
For instance, we may take the gene that assists the body to produce haemoglobin. In fact, haemoglobin is a vital protein that is essential for the red blood cells (RBC) to transport oxygen all over the body. Thus, if the parents pass on mutated or altered genes of haemoglobin to their child, the latter would only be able to produce a kind of haemoglobin that would not work as it should. In such a situation, the child may suffer from a condition known as anaemia, wherein an individual has just a few vigorous red blood cells.
Inherited anaemia may at times prove to be quite serious that may necessitate continuing medical care. In fact, one type of anaemia known as sickle cell anaemia is passed on from parents to children which requires long-term medical treatment.
Some children may inherit another ailment known as cystic fibrosis (CF) - an inherited chronic ailment of the exocrine glands, distinguished by the production of viscid mucus that blocks the pancreatic ducts and bronchi, resulting in contagion and fibrosis, from their parents. Individuals who suffer from cystic fibrosis may usually endure breathing problems since their body produces abundant of mucus - a slippery substance that is discharged from the nose when you blow, which is jammed in the lungs. Such people generally require medical treatment all through their life to keep their lungs free from mucus and also healthy.
Gene therapy involves the use of the genetic engineering technology in treating or healing an ailment caused by a gene that has changed in some way or the other. In other words, gene therapy is the medical procedure required to treat any disease caused by a mutated gene. Gene therapy is the latest type of medication and scientists are still continuing with experiments to find out if this medicine is effective. One of the methods being tested by the scientists is to replace the mutated or altered genes with healthy and vigorous genes. In fact, scientists are of the view that gene therapy trials - wherein the research is examined on people, as well as other researches may perhaps result in novel methods to treat as well as prevent several ailments - some of which may be caused by altered or mutated genes.
Precisely speaking, gene therapy may be described as a trial procedure that makes use of genes to prevent or treat ailments. Scientists are of the view that someday, gene therapy may permit doctors to treat a health condition by placing a gene inside the cells of the patient rather than resorting to the use of drugs or undertaking any operation!
Presently, scientists are experimenting with numerous methods of gene therapy, such as:
Nevertheless, gene therapy is not completely safe and effective. While gene therapy is being promoted as a favourable and encouraging treatment alternative for several diseases, such as inherited health conditions, certain viral infections and also specific types of cancer, this treatment procedure is still risky and presently being examined to ensure that it will be harmless as well as helpful. In fact, presently scientists and doctors are testing gene therapy only for such ailments which still do not have any known remedy.