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

Abstract

On 398 river buffalo samples, randomly collected in distinct breeding areas of the Campania region, high-resolution analytical 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 globin chains; restriction endonuclease analysis was performed to assess whether quantitative variations in Hb bands were related to an unusual number of α-globin genes. In the two buffalo subpopulations, allele frequencies of the alpha and beta globin systems were calculated, and F statistics (FIS, FIT and FST) were estimated as parameters of genetic diversity. The results suggest that: i) as shown by RFLP analysis, only a couple of associated α globin genes account for the quantitative variations recorded at the phenotypic level; ii) as expected, in the α 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) the frequency of the usual allele at the beta locus is 0.6, as opposed to 0.4 of the slow variant; iiii) the most significant component of variation of the genetic system of hemoglobin is between individuals within the same location.

Functional effect of haemoglobin polymorphism on the haematological pattern of Gentile di Puglia sheep

“…In agreement with what had been suggested in previous papers on sheep, buffalo and goat (Pieragostini et al. 2003; Iorio et al. 2004; Pieragostini et al.…”

“…In agreement with what had been suggested in previous papers on sheep, buffalo and goat Iorio et al 2004;Pieragostini et al 2005) and with the guidelines for gene nomenclature in ruminants (Andresen et al 1995), we suggest placing the superscript on the right with the upper case letter indicating the point mutation distinguishing the alleles to describe the as yet unnamed sheep agenes (Table 1). As to the nomenclature for the polypeptide chains, we followed the same pattern as described by Huisman & Schroeder (1971).…”

The haemoglobin subunits alpha and beta: Old and new genetic variants in the Italian Mediterranean buffalo

“…(The gene and protein variants have been named using as superscript letter the letter code indicating the substitution in the mature protein consequent to the mutation in the codons (Table 2). The superscript letter S assigned to the HB phenotype indicates the presence of the slow electrophoretic mobility of HB's carrying the β T variant; the phenotypes are obviously named according to the homozygosity at HBB subunits and to the fact that HBΑ diplotypes exhibit equal or different subunits) Luccia et al 1991a;Iorio et al 2004). Part C of Table 1 summarizes the tetramers observable depending on the haemoglobin electrophoretic phenotypes, which, in turn, depend on the genetic polymorphism at subunits alpha and beta.…”

“…Blood samples. Previously, a total of 398 adult animals had been randomly sampled in two breeding areas of the Campania region and analysed for HB polymorphism (Iorio et al 2004). Thereafter, nine individuals characterized by different HB phenotypes (Table 3) were selected in this study for DNA sequencing.…”

“…Thirdly, though the structure and organization of haemoglobin subunit clusters has been reported in many species, very little information is available about the genomic features of river buffalo. Finally, interesting protein polymorphisms in the haemoglobin genetic system have been found in Mediterranean buffalo (Di Luccia et al 1991a;Iorio et al 2004).…”