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Gene  Section on DNA that codes for specific information and genes. 

Gene Expression  Provides information about the activation of a gene, which leads to the

biosynthesis of a protein through transcription (RNA synthesis) and translation. 

Gene Ontology (GO)  Grouping of genes according to their species-specific known func­

tion in biological processes, cellular components and molecular function. Many tools use

this grouping for initial functional analysis and characterization of genes, such as the

Cytoscape plugin BiNGO (see BiNGO).

Genetic Algorithms  Search strategy in which solutions are bred in the computer using

artificial evolution through selection, mutation and recombination of digitally programmed

chromosomes (encode the problem). 

Genome  The entire genetic material (hereditary material, also called genome) and thus

all genetic information of an organism. Only viruses can exceptionally contain a genome

of RNA. Large organelles, especially mitochondria and chloroplasts, also contain DNA

and a small ring-­shaped DNA molecule (a few thousand nucleotides). This indicates their

descent from free-living bacteria (endosymbiont hypothesis). The genome of viruses is

typically a few thousand nucleotides in size (only the polymerase duplicates the genome),

that of bacteria a few million base pairs (polymerase and correction enzymes), and that of

higher organisms (with nucleus) several billion nucleotides (polymerase and sophisticated

correction pathways). 

Genomics  Analysis of the genome, the totality of all genes. 

Genome-­Wide Association Studies (GWAS)  Studies to identify genome-wide impor­

tant genes associated, for example, with a disease, in order to detect more precisely the

specific signal of mutations that are then important for the particular individual aspect

(disease, which exact subtype).

Genetic Shift  Random change of larger sequence regions or even entire genes that can

influence function, e.g. catalytic domain or functional site. In contrast, gene drift is a

smaller random change in allele frequency within the gene pool of a population. 

Global Alignment  Two sequences are compared with each other by comparing which

amino acid residues are modified and which are conserved. One can either compare over

the whole length or only a part of the sequence (see local alignment). For global align­

ment, there is an exact method, Needleman and Wunsch search, which is slow but accu­

rate, and various heuristic methods (inexact, but few errors and much faster). For example,

for phylogenetic methods, CLUSTAL search works fast.

Gödel, Gödel’s Incompleteness Theorem  see second Gödel’s incompleteness theorem.

18  Glossary