DNA Glossary

DNA Glossary


One of the four nucleobases found in DNA. Adenine (A) always pairs with thymine (T).


Alternate sequences for a particular position in the genome


Line of descent.


The study of the human race, its culture and society and its physical development


Of or having to do with an uncle

Certified laboratory

Officially recognised as meeting the essential requirements of a quality management system, a scientific facility equipped to conduct tests and investigations


Any of the rod-like structures found in all living cells, containing the chemical patterns which control what an animal or plant is like


One of the four nucleobases found in DNA. Cytosine (C) always pairs with guanine (G)


The statistical study of human populations especially with reference to size and density, distribution, and vital statistics.


Deoxyribonucleic Acid. Genetic information is encoded and transmitted from generation to generation in it. It is a coiled molecule organized into structures called chromosomes cells. Segments along the length of a DNA molecule form genes, the molecular laborers that carry out all life-supporting activities in the cell. Although all humans share the same set of genes, individuals can inherit different forms of a given gene, making each person genetically unique.


The description of a gene in a pair of genes that will produce a particular characteristic, regardless of the characteristic of the paired gene

Double Helix

The shape that two linear strands of DNA assume when bonded together


The basic unit of heredity; a sequence of DNA nucleotides on a chromosome

Gene frequency

The relative occurrence of a particular allele in a population

Gene mapping

Determination of the relative positions of genes on a DNA molecule (chromosome or plasmid) and of the distance, in linkage units or physical units, between them


The study of inheritance and the variation of inherited characteristics


One of the four nucleobases found in DNA. Guanine (G) always pairs with cytosine (C)


The process of passing on physical characteristics from one generation to the next


The process of examining your passport and other documents to make certain that you can be allowed to enter the country, or the place where this is done


(An act of) having sex with someone who is not your husband, wife or regular sexual partner, or (an example of) not being loyal or faithful

ISO 17025

An International Standard (published by the International Organization for Standardization) that specifies the general requirements for the competence to carry out tests and/or calibrations

Locus (pl. loci)

The specific physical location of a gene on a chromosome


A gene of known location on a chromosome and phenotype that is used as a point of reference in the mapping of other loci


Related to pregnancy and birth

Megabase (Mb)

Unit of length for DNA fragments equal to one million nucleotides


The techniques and practice of a midwife, a woman who is trained to assist women in childbirth


Any inheritable change in DNA sequence


The fact of being a father or connected with being a father

Physical map

A map of the locations of identifiable landmarks on DNA. Distance is measured in base pairs


Difference in DNA sequence among individuals. Genetic variations occuring in more than 1% of a population would be considered useful polymorphisms for linkage analysis


The period from conception to birth when a woman carries a developing fetus in her uterus


The activity of collecting information about someone, especially a criminal, in order to give a description of them


A large molecule composed of one or more chains of amino acids in a specific order; the order is determined by the base sequence of nuceotides in the gene coding for the protein. Proteins are required for the structure, function, and regulation of the body cells, tissues, organs, and each protein has unique functions


Degree of molecular detail on a physical map of DNA


The thick white fluid containing spermatozoa that is ejaculated by the male genital tract


Determination of the order of nucleotides (base sequences) in a DNA or RNA molecule or the order of amino acids in a protein

Sex chromosomes

Chromosomes that are different in the two sexes and involved in sex determination


A small piece of soft material used for cleaning a cut or for taking a small amount of substance from a body, or the substance itself which can then be tested


A pyrimidine base; one of the four molecules containing nitrogen present in the nucleic acids DNA and RNA; designated by letter T


A sex chromosome which exists as a pair in the cells of females and with a Y-chromosome in the cells of male animals


A sex chromosome that exists only in male cells


Short tandem repeats located on the Y chromosome