Sickling, A Quantitatively Delayed Genetic Character.

Abstract

Of 84 newborn Negro babies, 7 had positive sickling, with 3-15% sickling erythrocytes and S hemoglobin ranging from "not demonstrable" to 21%. Both of these values increased with age until at 4.5-7 months, they reached adult levels. One baby had 8% hemoglobin C, about 1/4 the adult value. Hemoglobin S (and C), like hemoglobin A, reaches full development only after the first few months of life. This explains the rarity of SCA and the paucity of sickling erythrocytes in young infants.