Variants of hemoglobin F and observations on hemoglobin F (Malta)

Abstract

The major hemoglobin component found in the blood of humans at birth is fetal hemoglobin, hemoglobin F. In common with most other human hemoglobins it has a tetrameric structure, each molecule being made up of two different pairs of polypeptide chains. At birth hemoglobin F accounts for 60-80% of the hemoglobin present in the blood. Hemoglobin F-Malta is the most recent variant discovered and is of special interest to Malta as it is only here that it has been reported (Cauchi et aI., 1969). Hemoglobin F-Malta is unique among the fetal variants in that it has a very high incidence, being present at birth in the blood of one Maltese child in every fifty. The variant disappears as the baby matures, in common with other fetal hemoglobin variants, and has not been observed in any parents. Infants born with hemoglobin F-Malta are apparently healthy and have no other hematological anomalies. The results of an ongoing study on the relative rates of disappearance of the hemoglobins F-Malta and F as the infants mature are displayed. Because of the high incidence of hemoglobin F-Malta it is possible to carry out a much more comprehensive study on the relative rates of disappearance than it is in the case of other fetal variants.