Hemoglobin D-Punjab Homozygotes and Double Heterozygotes in Premarital Screening: Case Presentations and Minireview

Hemoglobin D-Punjab is the most common variant of hemoglobin D. In premarital screening, molecular testing is often unavailable, and diagnosis (and marriage guidance) often relies on the hemoglobin analysis, family studies and epidemiological facts. The use of latter methods sometimes results in hemoglobin D-Punjab/β-thalassemia double heterozygote being mistaken for its homozygote, which could be costly. We present the clinical and laboratory characteristics of hemoglobin D-Punjab phenotypes/genotypes in 15 individuals and review similar reports in the literature. We find that the quantity of hemoglobin D-Punjab in homozygotes is higher than in hemoglobin D-Punjab/β-thalassemia double heterozygotes, its fraction > 92% being consistent with homozygosis. The limitations of this diagnostic criterion are discussed, and clinical severity of this and other hemoglobin D-Punjab double heterozygotes reviewed.