Biochemical and molecular investigations on qualitative and quantitative Hb polymorphism in the river buffalo (Bubalus bubalis L.) population reared in Southern Italy

On 398 river buffalo samples, randomly collected in distinct breeding areas of the Campania region, high-resolutionanalytical systems were used to identify both qualitative and quantitative variations of the Hb phenotype.Polyacrylamide gel isoelectric focusing and HPLC were used to determine the ratio between HBA1 and HBA2 globinchains; restriction endonuclease analysis was performed to assess whether quantitative variations in Hb bands wererelated to an unusual number of ?-globin genes. In the two buffalo subpopulations, allele frequencies of the alphaand beta globin systems were calculated, and F statistics (FIS, FIT and FST) were estimated as parameters ofgenetic diversity. The results suggest that: i) as shown by RFLP analysis, only a couple of associated ? globin genesaccount for the quantitative variations recorded at the phenotypic level; ii) as expected, in the ? globin gene system(HBA), the frequency of haplotype B (HBA-B) largely exceeded that of haplotype A (HBA-A) (95.1% vs 4.9%); iii) thefrequency of the usual allele at the beta locus is 0.6, as opposed to 0.4 of the slow variant; iiii) the most significantcomponent of variation of the genetic system of hemoglobin is between individuals within the same location.