MAPPING DNA POLYMORPHISMS USING PCR PRIMERS DERIVED FROM THE SEQUENCEOF AN AVIAN CR-1 ELEMENT

Primers complementary to the chicken middle repetitive sequence elemen t CR1 were used to generate and simultaneously map polymorphic polymer ase chain reaction products (CR1-PCR) with various chicken DNAs as tem plates. Ten primers were prepared using the sequence of a single CR1 e lement as a guide. These 10 primers generated 23 polymorphic CR1-PCR p roducts. The average number of polymorphic CR1-PCP products generated using single primers (1.1 per primer) was significantly higher than th e average number observed using combinations of two primers (0.3 per p rimer combination). The polymorphic CR1-PCR products were mapped in a subset of a reference backcross population designed for the genetic li nkage analysis of the chicken. Nineteen of the polymorphic CR1-PCR pro ducts identified were assigned to 13 of 19 linkage groups characterize d thus far in this population; three have yet to be linked to a specif ic map location. One of the CR1-PCR markers mapped to the chicken Z ch romosome. There was no evidence for a significant clustering of CR1-PC R markers within the map, even at the site of the CR1 element whose se quence was used for primer design.