glossary
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Map distance
The distance between genes expressed as map units or centiMorgans (cM).
Marker
Marker can refer to a gene with a known location on a chromosome and a clear-cut phenotype, that can be used as a point of reference when mapping a new mutant or antigenic markers that serve to distinguish cell types
Mass spectrometry
Technique used to measure and analyse a substance in terms of the ratios of mass to charge of its components.
MEMS
MicroElectroMechanical Systems. Today, it usually relates to a microsystem that is integrated in a chip. Originally, MEMS technology was mainly used in the semiconductor industry.
Methylation
Methylation of cytosine (usually in CG stretches) --> sign for transcription factors to activate the gene and thus produce a protein. It is generally understood that genes that are available for transcription are sometimes less heavily methylated than the same genes in cells in which they are never expressed. It also refers to the addition of a methyl group to a chemical compound or macromolecule.Microarray
Arrangement of miniaturised test sites on a small surface; spot sizes are usually less than 250µm. Many tests can be performed simulatenously or in parallel.
Microfluidics
Handling of volumes of liquids as small as 0.1 nanoliter.
Microfluidics chips
The chips contain very tiny channels in which the movement of fluids can be controlled. They allow the intergration and miniaturisation of many laboratory processes. Due to the tiny size, only low quantities of chemicals and test materials are required.Microtransponder
Cube-shaped (~100µm), miniature radio-frequency transmitters out of silicon. The transponder has a memory and emits characteristic radiofrequencies upon activation (in this case by a laser).Molecular imprinting
Process by which functinal monomers can self-assemble around a template molecule. Afterwards they are cross-linked into place. The template molecule can be removed under defined conditions. A cavity is thus left behind which is complementary in shape and functionality. Molecules can be bound which are identical to the template.
mRNA
messenger RNA; RNA molecule that functions during translation to specify the sequence of amino acids in a nascent polypeptide. In eukaryotes, mRNA is formed in the nucleus from premessenger RNA molecules.
Multifactorial disease
Polygenic disease, i.e. disease determined by the action of several independent genes.Multiplex
This word is mainly used as 'multiplexing', thus referring to a method by which many parameters are simultaneously tested and processed.Mutation
Change in the structure of DNA, thus leading to a change in the characterstics of an organism or indivudal cell as a result of altered protein or RNA content specified by the mutated DNA. One can differentiate for example between silent mutations, point mutations, back mutations, or somatic mutations.