Genomics Glossary

One of two or more alternative forms of a gene that arise by mutation and are found at the same position on a chromosome.

A unit of double-stranded DNA consisting of two complementary nucleotides bonded together (A-T or G-C).

The application of computational tools and statistical methods to the analysis and interpretation of biological data, especially sequences.

The complex of DNA and histone proteins that forms chromosomes. Chromatin structure regulates gene accessibility and expression.

A threadlike structure of DNA and associated proteins that carries genetic information. Humans have 23 pairs of chromosomes.

A sequence of three nucleotides in mRNA that specifies a particular amino acid or a stop signal during protein synthesis.

A contiguous stretch of DNA sequence assembled from overlapping shorter reads during genome assembly.

Clustered Regularly Interspaced Short Palindromic Repeats. A genome-editing system adapted from bacterial adaptive immunity.

The study of heritable changes in gene expression that do not involve alterations to the DNA sequence itself.

A segment of a gene that is transcribed and retained in the final mature mRNA molecule after splicing.

The genetic constitution of an organism, specifically the set of alleles it carries at one or more loci.

A set of genetic variants (alleles) on a single chromosome that tend to be inherited together.

A non-coding segment of a gene that is transcribed into RNA but removed by splicing before translation.

The specific physical position of a gene or genetic marker on a chromosome.

The addition of a methyl group to DNA, typically at cytosine bases. A key epigenetic mechanism that generally silences gene expression.

A technology using thousands of DNA probes on a solid surface to simultaneously measure expression levels of many genes.

A permanent change in the DNA sequence. Can be beneficial, neutral, or harmful depending on context and location.

The basic building block of DNA and RNA, consisting of a sugar, a phosphate group, and a nitrogenous base (A, T, G, or C in DNA).

The observable physical or biochemical characteristics of an organism, determined by genotype and environment.

A technique for amplifying specific DNA sequences by repeated cycles of denaturation, annealing, and extension.

A regulatory DNA sequence located upstream of a gene that initiates and controls transcription.

A standardized representative genome sequence for a species, used as a baseline for comparison in sequencing studies.

A biological process in which small RNA molecules inhibit gene expression by targeting complementary mRNA for degradation.

The process of copying a segment of DNA into messenger RNA (mRNA) by the enzyme RNA polymerase.

The process of determining the complete DNA sequence of an organism's genome in a single sequencing effort.