The development and mapping of functional markers in Fragaria and their transferability and potential for mapping in other genera.

We have developed 46 primer pairs from exon sequences flanking polymorphic introns of 23 Fragaria gene sequences and one Malus sequence deposited in the EMBL database. Sequencing of a set of the PCR products amplified with the novel primer pairs in diploid Fragaria showed the products to be homologous to the sequences from which the primers were originally designed. By scoring the segregation of the 24 genes in two diploid Fragaria progenies FV x FN (F. vesca x F. nubicola F(2)) and 815 x 903BC (F. vesca x F. viridis BC(1)) 29 genetic loci at discrete positions on the seven linkage groups previously characterised could be mapped, bringing to 35 the total number of known function genes mapped in Fragaria. Twenty primer pairs, representing 14 genes, amplified a product of the expected size in both Malus and Prunus. To demonstrate the applicability of these gene-specific loci to comparative mapping in Rosaceae, five markers that displayed clear polymorphism between the parents of a Malus and a Prunus mapping population were selected. The markers were then scored and mapped in at least one of the two additional progenies.