Methods to detect QTLs: single point regressions
There are a number of statistical methods used for QTL identification. The simplest, and probably most common, is the single point (ie. single marker) linear regression.
As in the previous example from Young, this approach looks at every marker-trait combination, one marker at a time. Using a linear regression statistical test (as opposed to a simple t-test, for example) gives the additional information of the phenotypic variance (R2) of that QTL – that is, how much of the phenotypic variation is associated with that specific QTL. An example is shown on the next slide.