IDENTIFICATION AND GEOGRAPHICAL DISTRIBUTION
 OF ALLELES AT LOCUS 178


 Introduction


 Nuclear DNA restriction fragment length polymorphisms (RFLPs) are

 biparentally inherited, codominantly expressed markers shown to be a valuable

 source of genetic variability in honey bees (Hall 1986, 1990, 1992b). Relative

 to the biochemical variability that can be discerned in allozyme frequencies,

 RFLPs are more abundant and do not require gene expression for their

 detection. East European- and African-specific RFLP markers have been

 identified, as well as markers common to African and a west European species

 (Hall 1986, 1990, 1992b). In neotropical colonies, the east European markers

 have been found at very low frequencies in areas where African bees have

 become established, indicating that there has been limited paternal introgression

 from European colonies into the African bee population (Hall 1990). One

 limitation to date in the use of RFLPs to study ancestry in neotropical bees has

 been the lack of additional markers specific for other subspecies, particularly

A. m. mellifera.

 Described in this chapter are nuclear DNA RFLPs, detected with a single

genomic probe, that distinguish bees of European and African ancestry. While