Fundamental Genetics Terminology Explained

Gene

A gene is an organized, linear sequence of nucleotides in a DNA molecule that contains the information necessary for the synthesis of a macromolecule with a specific cellular function.

Genome

The genome is the entire set of genes of an individual or species, contained in a haploid set of chromosomes.

Genotype

The genotype is the sum total of the genetic information contained in an organism's chromosomes.

Karyotype

A karyotype is a schematic, photograph, or drawing of the metaphase chromosomes of a cell, arranged according to their morphology and size. The karyotype is characteristic of each species, as is the number of chromosomes, and it represents all individuals of that species.

Natural Selection

Natural selection is the process by which species best adapted to their environment survive and reproduce, while others are extinguished. It is the basis of all evolutionary change.

Genetic Mutation

A genetic mutation is an alteration or change in the genetic information of a living being. This change in its characteristics occurs suddenly and spontaneously and can be transmitted or inherited by the progeny. The genetic unit capable of mutation is the gene, which is the fundamental unit of hereditary information that is part of DNA.

Chromosome

A chromosome is one of the small, rod-shaped bodies in which chromatin is organized within the cell nucleus during cell division (mitosis and meiosis). Chromatin is the material that carries the genetic information of eukaryotic organisms and consists of DNA associated with proteins.

Genetic Code

The genetic code is the key information within genes that expresses the universal correspondence between the sequence of nucleic acids and the sequence of proteins. It forms the basis for the transmission of hereditary traits.

Watson and Crick

James Watson and Francis Crick created the double-helix model of DNA and received the Nobel Prize in Physiology or Medicine in 1962. Their discovery caused a revolution in the biological sciences that continues to this day with ongoing scientific breakthroughs.

Human Genome Project

The Human Genome Project was an international scientific research project with the primary goal of determining the sequence of chemical base pairs that make up DNA and to identify and map the approximately 20,000-25,000 genes of the human genome from both a physical and functional standpoint.