Tuesday, March 8, 2011

Because of the technological investments required, genetic analyses have traditionally been applied to only a small set of model species, such as nematode worms or fruit flies, which have short life spans and are amenable to experimental manipulation. These organisms typically represent abstractions of biological systems, so it has been difficult to infer from these studies how species in the wild interact with their natural surroundings. Moreover, although traditional genetics has focused on the action of single genes with discrete phenotypic effects, the traits that determine the interactions of organisms with their environment are usually controlled by multiple genes producing a continuum of phenotypes (Fig. 1). New combinations of genetic and genomic approaches applied in the context of natural populations now provide a means to trace the genetic basis of adaptation and the interactions of organisms with their environment1-3.

Janne Lempe and Detlef Weigel, Max Planck Institute for Developmental Biology.
Quantitative trait locus (QTL) analysis is used to examine a continuous trait in a natural or experimental population. It identifies multiple stretches of DNA in the population’s genome that are associated with the trait in question as a first step towards identifying the contributing genes. A more recent alternative is the genome-wide association study (GWAS), which compares phenotypic information in a natural population against a panel of sequence markers throughout the genomes of thousands of individuals4.Through statistical association, genomic regions that correlate with the trait of interest can be identified.

>> Ecological genomics is unifying disparate biological disciplines to provide a clearer understanding of patterns in biodiversity .

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Publisher and/or Author and/or Editor:__Andres Agostini ─ @Futuretronium at Twitter! Futuretronium Book at http://3.ly/rECc