Genetics and genomics

Although inherited of traits has been observed throughout history the modern science of genetics was pioneered by Gregor Mendel in the 19th century. Genes are the most basic unit of inheritance; they contain a nucleotide sequence coding for a gene product (protein or RNA). Genetic variation is acquired primarily from mutations but also from other sources such as genetic recombination, sexual reproduction and genetic drift. Genetic variation results in different forms of genes called alleles.

DNA (deoxyribonucleic acid) is the double helical molecule that carries the genetic instructions for all known organisms and some viruses. The DNA molecule was discovered by Dr Friedrich Miescher in 1869. Based on an X-ray diffraction image named ‘Photo 51’ taken under the supervision of Rosalind Franklin; James Watson and Francis Crick published their work on the double helical structure of DNA in 1953. DNA is organized into structures called chromosomes; the number of chromosomes varies between species.

A genome refers to an organism’s complete set of DNA including all genes and its structural configuration. Genomics is the field of study focused on the structure, function, mapping, evolution and editing of genomes. Genomics looks at the overall characterization and quantification of all an organism’s genes, their relationships and influence on the organism.

The science of genetics and genomics has greatly influenced medicine and research. For example, the genetics and genomics have aided understanding of genetic disorders, developing gene therapies and personalized medicine and genetic counseling.