Genetic similarity maps and immunoglobulin allotypes of eleven populations from the Pyrenees (France).

The genetic heterogeneity of eleven populations from the Pyrenees (France) based on the polymorphism of the immunoglobulin allotypes is studied by means of a 'genetic similarity map'. The method described here, called 'Mobile Node Method', allows the deformation of a square grid, in which the studied region is represented, by moving the nodes at each step in order to reduce the difference between the geographic and genetic distances. This tool allows the overall quantification of the genetic heterogeneity of a population set and possibly the study of its dynamics. Other maps constructed to complete the interpretation are 'map of moving vectors', 'iso-displacement curves' and 'site displacements'. This study identified an overall genetic homogeneity among the Pyrenean populations and several local genetic heterogeneities in different regions.