Haptoglobin DNA polymorphism in subterranean mole rats of the Spalax ehrenbergi superspecies in Israel.

We analyzed the genetic diversity and environmental correlates of the haptoglobin (Hp) gene by RFLP analysis of 121 subterranean mole rats, comprising 13 populations belonging to the 4 chromosomal species (2n = 52, 54, 58 and 60) of the actively speciating Spalax ehrenbergi superspecies in Israel. The following results were indicated: (i) Out of the six restriction enzymes we tested, we found polymorphism only in TaqI, with three allelic fragments, and described their geographic patterning. (ii) Genetic diversity of Hp was highest in the centre of the range. (iii) The two major alleles showed high significant and opposite correlation with humidity. (iv) Genetic differentiation analysis indicated that 40 per cent of the Hp variation was within, and 60 per cent between populations. We conclude that climatic selection plays an important role in haptoglobin genetic differentiation.