The two genes homologous to Arabidopsis FAE1 co-segregate with the two loci governing erucic acid content in Brassica napus

KCS (beta-keto-acyl-CoA synthase) has been proposed as a candidate gene for explaining the erucic acid level in rapeseed. Degenerate PCR primers corresponding to the FAE1 gene have been designed. Two B. napus genes BN-FAE1.1 and BN-FAE1.2, corresponding to the parental species B. I apa and B. oleracea FAE1 genes, were amplified. Polymorphism was revealed for these two genes by acrylamide electrophoresis of the amplification products. These two genes could then be mapped and a co-segregation of these genes with the El and E2 loci controlling erucic acid content was found. Furthermore, mutations observed for one of these genes could explain part of the low erucic trait of the three LEAR types used in this study.