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Genetics and Genomics Glossary

The following glossary was obtained with permission from the following resource: Allendorf, F.W., and G. Luikart. 2007. Conservation and the Genetics of Populations. Blackwell Publishing. 642 pp.



cDNA
Complementary DNA.

census population size
The number of individuals in a population.

centromere
An constricted region of a chromosome containing spindle microtubules responsible for chromosomal movement during mitosis and meiosis.

chi-square test
A test of statistical significance based on the chi-squared statistic, which determines how closely experimental observed values fit theoretical expected values.

chloroplast DNA (cpDNA)
A circular DNA molecule located in chloroplasts. Forty to 80 copies occur per organelle and replication occurs throughout the cell cycle.

chromosome
A molecule of DNA in association with proteins (histones and non-histones) constituting a linear array of genes. In prokaryotes, the circular DNA molecule contains the set of instructions necessary for the cell.

CITES
Convention on International Trade in Endangered Species of Wild Fauna and Flora.

clade
A species, or group of species that has originated and includes all the descendents from a common ancestor. A monophyletic group.

cladistics
The classification of organisms based on phylogeny.

cladogenesis
The splitting of a single evolutionary lineage into multiple lineages.

cladogram
A diagram illustrating the relationship between taxa that is built using synapomorphies. Also called a phylogeny.

cline
A gradual directional change in a character across a geographic or environmental gradient.

coalescent
The point at which the ancestry of two alleles converge at a common ancestral sequence.

codon
A three nucleotide sequence on a strand of mRNA that gets translated into a specific amino acid forming a protein.

conservation breeding
Efforts to manage plant and animal species breeding that do not necessarily involve captivity.

conservation collections
Living collections of rare or endangered organisms established for the purpose of contributing to the survival and recovery of a species.

conspecific
A member of the same species.

continuous characters
Phenotypic traits that are distributed continuously throughout the population (e.g., height or weight).

continuous distribution model of migration
Individuals are continuously distributed across the landscape; neighborhoods of individuals exist that are areas within which panmixia occurs, and across which genetic differentiation occurs due to isolation by distance.

Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)
An agreement among 145 countries that bans commercial international trade in an agreed-upon list of endangered species, and that regulates and monitors trade in others that might become endangered.

converged
The point where a MCMC simulation has become independent of starting parameter biases, or has been “burnt in”. Typically, thousands of simulation steps are required (and discarded) before the MCMC simulation is used to estimate a parameter (e.g., Ne, Nm, etc.)

countergradient variation
Occurs when genetic effects on a trait oppose or compensate for environmental effects so that phenotypic differences across an environmental gradient among populations are minimized.

cpDNA
See
chloroplast DNA.

CU
Conservation unit.

cultivars
A human-cultivated plant that was derived through athropogenenic selection.

cytogenetics
A discipline of science combining cytology, the study of cells (their structure, function, and life history), and genetics.

cytoplasmic genes
Genes located in cellular organelles such as mitochondria and chloroplasts.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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