Postnatal changes in the quantities of globin chains and hemoglobin types in two babies with Hb H disease.
We have studied two babies with Hb H disease from birth to about six months of age and analyzed the changes in the relative quantities of the five globin chains (zeta, alpha, beta, G gamma, A gamma) and the four hemoglobins (Hb F, Hb A, Hb Bart's, Hb H) using different high performance liquid chromatography procedures. The types of Hb H disease were -(SEA)/-alpha(3.7 kb) and -(Fil)/-alpha(3.7 kb); the larger -(Fil) deletion includes the functional zeta 2-globin gene, explaining the higher zeta chain level in the baby with the -(SEA)/-alpha(3.7 kb) type. The functional hemoglobin level at birth (Hb A+Hb F) was 11 to 12 g/dl with 3 to 4 g/dl Hb Bart's (gamma 4). Only 5% of the "fast-moving" hemoglobin was Hb H (beta 4). The level of Hb F at birth was low (less than 50% of the total Hb A+Hb F). After birth, the alpha and gamma chain production decreases rapidly resulting in a severe anemia (total functional hemoglobin approximately 7 g/dl) at 30 to 60 days postnatally, improving gradually to 8.5-9.5 g/dl at age of three months. The preferential formation of Hb A over Hb F at birth, and presumably prenatally, has the advantage that the level of the highly unstable Hb H is kept low; it also results in low levels of Hb F impairing the oxygen transfer capability of the fetal blood.
McKie
K M
KM
Department of Pediatrics, Medical College of Georgia, Augusta 30912-2100.
Gu
L H
LH
Gu
Y C
YC
Huisman
T H
TH
D000375:Aging / Q000097:blood*; D005260:Female; D005312:Fetal Blood; D017353:Gene Deletion; D005914:Globins / Q000737:chemistry*; D006402:Hematologic Diseases / Q000097:blood* / Q000235:genetics; D006447:Hemoglobin H; D006454:Hemoglobins / Q000737:chemistry*; D006801:Humans; D007231:Infant, Newborn / Q000097:blood* / Q000254:growth & development; D008297:Male
D006454:Hemoglobins; D005914:Globins; D006447:Hemoglobin H