Study of Red Blood Cell and Serum Enzymes in Five Pyrenean Communities and in a Basque Population Sample

Until recently, no data on genetic polymorphisms in the populations living on the northern side of the Pyrenees have been available, except for the Basques. Several investigations were done lately on rural communities in various geographic zones in the Pyrenees from the eastern to the western part. In this paper, the results for the following enzyme polymorphisms are reported: acid phosphatases, AK, ADA, PGM₁ and PGM₂, 6PGD, NADH diaphorase, SOD, MDH, TGP, G6PD, C₅ esterase (E₂ locus), serum cholinesterase (E₁ locus). Significant variation in gene frequencies was observed over the distinct geographic zones for the main polymorphic system. Furthermore, some rare alíeles were found: a new G6PD variant (Luz-Saint-Sauveur), the presence of ADA³ and ADA⁵ alleles in two groups of the Central Pyrenees, a Dia² gene among Basques and in the Pays de Sault, a high rate of Eª₁ allele in the Basque group. The values obtained for the degree of heterozygosity are in agreement with the relative isolation of the different groups studied and confirm the importance of sociocultural factors in the evolution of the genetic background of rural communities in Europe.