Genotyping

From Wikipedia, the free encyclopedia

Genotyping refers to the process of determining the genotype of an individual with a biological assay. Current methods of doing this include PCR, DNA sequencing, ASO probes, and hybridization to DNA microarrays or beads. The technology is important in clinical research for the investigation of disease-associated genes.

Due to current technological limitations, almost all genotyping is partial. That is, only a small fraction of an individual’s genotype is determined. New innovations, like the Human-1 BeadChip developed by Illumina or mass-sequencing technologies, promise to provide whole-genome genotyping in the future.

Genotyping applies to a broad range of "individuals" including microorganisms. Viruses for instance, or bacteria, can be genotyped. Genotyping in this context may help in controlling the spreading of pathogens, by tracing the origin of outbreaks. This area is often referred to as molecular epidemiology or forensic microbiology.

The "individuals" can also be human beings. When testing for father-/motherhood for instance, scientists typically only need to look at 10 or 20 genomic regions (like Single nucleotide polymorphism (SNPs) to determine relationship or lack thereof. That is a tiny fraction of the human genome, which consists of three billion or so nucleotides.

When genotyping transgenic organisms, a single genomic region may be all that scientists need to look at to determine the genotype. The mouse is the mammalian model of choice for much of medical research today. A single PCR assay is typically enough to genotype a transgenic mouse. Companies that provide mouse genotyping services includeTransnetyx,Taconic, GeneTyper,and Mouse Genotype LLC.