Editing Quantitative trait locus (section)

{{short description|DNA locus associated with variation in a quantitative trait}}
{{Use dmy dates|date=February 2020}}
A '''quantitative trait locus''' ('''QTL''') is a [[Locus (genetics)|locus]] (section of [[DNA]]) that correlates with variation of a [[quantitative trait]] in the [[phenotype]] of a [[Population genetics|population]] of [[organism]]s.<ref>{{Cite journal|url = http://www.nature.com/scitable/topicpage/quantitative-trait-locus-qtl-analysis-53904|title = Quantitative trait locus (QTL) analysis|last1 = Miles|first1 = C|date = 2008|journal = Nature Education|volume = 1|first2 = M|last2 = Wayne|issue = 1}}</ref> QTLs are mapped by identifying which molecular markers (such as [[single-nucleotide polymorphism|SNP]]s or [[amplified fragment length polymorphism|AFLPs]]) correlate with an observed trait. This is often an early step in identifying the actual [[gene]]s that cause the trait variation.