Molecular characterization of hemoglobin C in Sicily.
Analysis of polymorphisms of the beta-globin gene cluster was performed on 12 families and on one unrelated individual of Sicilian origin who carried hemoglobin C (Hb C). Two different haplotypes were found in association with beta c Sicilian alleles, corresponding to haplotypes I and II previously described in American blacks. In our population, the more frequent one (haplotype I) was linked to the lack of a polymorphic HpaI site 3' to the beta gene (13.0-kb fragment), similarly to haplotype I in blacks, while the less frequent one was linked to a 7.0-kb HpaI fragment attributable to a site that had never been previously described in linkage with beta c alleles. In Italy, these two haplotypes have been found in rare cases in association with beta A alleles. These findings provide new insights into the origin of Hb C present in Sicily, suggesting that (1) the beta c mutation detected in Sicily derived from African black chromosomes and does not represent a new mutation; and (2) Hb C may have originated either by multiple mutational events on separate chromosomes or by mutation in the HpaI site 3' to the beta gene in a pre-existing beta c chromosome.
Istituti Clinici di Perfezionamento, Laboratorio di Ricerche Cliniche, Milan, Italy.
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Ferrari
D000483:Alleles; D044383:Black People / Q000235:genetics; D004247:DNA / Q000235:genetics; D008040:Genetic Linkage / Q000235:genetics; D005914:Globins / Q000235:genetics; D006239:Haplotypes / Q000235:genetics; D006444:Hemoglobin C / Q000235:genetics*; D006801:Humans; D005810:Multigene Family / Q000235:genetics; D011110:Polymorphism, Genetic / Q000235:genetics; D012150:Polymorphism, Restriction Fragment Length; D012802:Sicily / Q000208:ethnology
D005914:Globins; D004247:DNA; D006444:Hemoglobin C