POSTNATAL CHANGE OF HEMOGLOBINS F AND A2 IN INFANTS WITH DOWN'S SYNDROME (G TRISOMY)

Hemoglobins F (fetal hemoglobin) and A2 were determined by column chromatography in 12 infants with Down9s syndrome (G trisomy). Comparison data were obtained from 48 normal term infants, of which 13 were followed throughout early infancy. None of the infants were significantly premature or postmature; and none possessed S or C hemoglobins. With one exception, infants with Down9s syndrome were found to have low hemoglobin F throughout the first several months of life and relatively elevated hemoglobin A2 for this duration of time. These findings are the direct opposite of the hemoglobin changes in D trisomy syndrome.