Molecular genetics is a sub-discipline of genetics, a field within the biological sciences. Genes are units of heredity, instructions for inherited traits such as hair color, blood type, and predisposition to some diseases. Molecular genetics is concerned with the physical and chemical properties of these genes.
Organisms depend on cells to grow and function. Each cell is essentially like a machine, following the instructions of its genes in order to run efficiently. The molecule that makes up genes is called deoxyribonucleic acid (DNA), which is stored inside the cells of organisms.
DNA is a long molecule, coiled tightly into structures called chromosomes. These chromosomes require strong magnification in order to be viewed. When viewed uncoiled, the DNA molecule resembles a twisted ladder, with two interwoven strands called a double helix. DNA’s double helix structure is a huge part of molecular genetics.
The field is also concerned with the structure and function of ribonucleic acid (RNA), a molecule essential to the running of cells. Structurally, RNA is quite similar to DNA, but they have different functions. The information in the cell’s DNA is copied to an RNA molecule, following which a protein designed for a specific task is assembled. In the human body, for example, a protein called hemoglobin allows red blood cells to carry oxygen to the body’s systems. The action of a gene producing a protein is called gene expression.
Gene mutations are changes in DNA that happen at a chemical level, and are also of interest in the field of molecular genetics. The genetics of cancer, in particular, is an area that is studied by molecular geneticists, who undertake research to better understand - and perhaps even prevent or cure - the disease. Gene therapy also calls for molecular geneticists. This type of therapy involves giving people new genes, and is an area being researched for the treatment of some diseases. Genetic engineering and cloning also come under the heading of molecular genetics.
Molecular geneticists often work in a laboratory environment, though they may also undertake roles that are research or teaching-based. Depending on the country in which they complete their education, molecular geneticists usually hold a bachelor’s degree in genetics and often an advanced degree, such as a PhD, as well. Some are also medical doctors who go on to specialize in genetics. In addition to specialists, a wide range of professionals in science, health, and education may come across this field of genetics in their working lives.