In a paper entitled, “Hybridization between crops and wild relatives: the contribution of cultivated lettuce to the vigor of crop–wild hybrids under drought, salinity and nutrient deficiency conditions,” published in the June issue of Theoretical and Applied Genetics,Brigitte Uwimana and associates investigated the vigor of lettuce hybrids of crosses, cultivated lettuce, Lactuca sativa X its wild relative L. serriola under both normal- and stress conditions such as those of drought, salinity and nutrient deficiency. Using single nucleotide polymorphism markers, they mapped quantitative trait loci associated with plant vigor in the F2:3 families and determined the allelic contribution of the wild parent and the cultivar to vigor. Their study revealed that there are 17 QTLs derived from both the parents that are associated with vigor and six QTLs associated with the accumulation of Na+, K+ and Cl− ions. The 23 QTLs were mapped on the nine linkage groups of lettuce. Based on the allelic effect of the QTLs and their location on the genetic map, the authors have suggested that integration of transgene should be avoided where its persistence may prove hazardous to human health.