Genetic diversity of the west European honey bee (Apis mellifera mellifera and A. m. iberica). II. Microsatellite loci

The genetic variability and differentiation of west European honey bee populations (Apis mellifera mellifera and A. m. iberica) have been investigated using 11 microsatellite loci. These two subspecies are characterised by a lower genetic variability than most other studied subspecies and several tests are indicative of a recent increase of the population size. Moreover, the genetic profiles are rather homogeneous from southern Spain to Scandinavia. French populations are more or less introgressed (a few percent up to 57 %) by genes from the north Mediterranean lineage which provides most of the imported queens. The inferred percentage of introgressed nuclear genes is generally well correlated with the proportion of alien mitochondrial deoxyribonucleic acid (mtDNA) haplotypes detected in the same populations. The level of introgression is the main source of genetic distances among populations. When introgressed genes are disregarded, however, populations cluster in two groups which correspond to both subspecies ( iberica and mellifera), giving full support to the taxonomy of this lineage. (C)Inra/Elsevier, Paris