Hemoglobin FHouston: A Fetal Variant

A fetal hemoglobin variant, designated hemoglobin F_Houston, was found inthe cord blood sample of a healthy, term Negro infant. The variant, comprising about 15 per cent of the total cord blood hemoglobin, diminished concomitantly with hemoglobin F, and it was barely detectable in the blood whenthe infant was 4 months old. The hemolysates of the parents and two siblingsresolved into the usual adult pattern, but a trace amount of a fraction similarto hemoglobin F_Houston was present in the father’s hemolysates and not in themother’s.

The ultraviolet absorption spectrum indicates that hemoglobin F_HOUSTON contains polypeptide chains, and immunologic studies reveal the presence ofboth and chains. In hybridization tests the alteration appears in the chain.

Peptide chromatograms of hemoglobin F_Houston indicated the presence of and chains, but failed to reveal an abnormality. Amino acid analyses suggestthat there may be a substitution of an alanyl for a glutamyl residue.

Submitted on August 3, 1965 Accepted on October 12, 1965