Hemostatic complications of cardiopulmonary bypass

The-117(G→A) ^Aγ hereditary persistence of fetal hemoglobin (Greek HPFH) and β⁰39-thal mutations are rather frequent in Sardinia so that their interaction is to be expected. Characterization of eight compound heterozygotes for these defects indicated that HPFH was linked to haplotype VII and β⁰39-thal to haplotype II. Haplotype II β⁰39-thal chromosome carries the ^Aγ^T gene which is a useful marker of γ-gene expression. Since the Hb F level in these compound heterozygotes was significantly higher than in 46 ?117 HPFH carriers, the ^Aγ^t, and ^Gγ globin level was determined. ^Aγ^T was underexpressed while ^Gγ was significantly increased, which suggests that in ?117 ^Aγ HPFH/β⁰39-thal healthy subjects the increase in Hb F production is determined only by the ?117 mutated ^Aγ gene and the adjacent ^Gγ gene. © 1995 Wiley-Liss, Inc.