Allozyme Variation in Wild Rats Rattus norvegicus (BERICENHOUT 1769) (Mammalia: Rodentia) from Turkey

Abstract

The genetic diversity of 22 allozyme loci was investigated in 33 wild rat (Rattus norvegicus) specimens from 4 sub-populations. Eight of the 22 loci (Pgm, Hk, Me-M, Ldh, alpha-Gpdh-1, alpha-Gpdh-2, Fum, Xdh) were polymorphic. The level of genetic variation was measured by mean number of alleles per locus (A = 1.18), percentage of polymorphic loci (P = 18.2), mean heterozygosity per locus observed (Ho = 0.007), and mean heterozygosity expected under Hardy - Weinberg equilibrium (He = 0.057). Mean Psi, value was 0.34, indicating 34% genetic variation and suggesting high-level differentiation between sub-populations of the Turkish wild rat. The number of migrants (Nm) was 0.48 and showed that gene flow was relatively low between sub-populations. Even though a high level of genetic variation was observed, the low Nm value and Ho could be evidence of the Wahlund effect or a genetic bottleneck for the sub-populations. It is also suspected that there might be some factors preventing gene flow from the sub-populations, which constitute their own genetic potential for new taxonomic units.