Hb C-Harlem | beta6(A3)Glu->Val; |
---|---|
beta73(E17)Asp->Asn |
HEMATOLOGY | Normal in the heterozygote | ||
ELECTROPHORESIS | Hb X moves like Hb C in standard electrophoresis at alkaline pH; at acidic pH (agar gel) Hb X occupies the position of Hb S | ||
CHROMATOGRAPHY | Hb X elutes with Hb A2 in anion exchange chromatography; Hb X also separates from Hb A on a CM-Sephadex column | ||
STRUCTURE STUDIES | Tryptic digestion of AE-betaX chain; separation of peptides by fingerprinting; amino acid analysis; sequencing | ||
DNA ANALYSES | Not reported; presumed mutations GAG->GTG and GAT->AAT at codons 6 and 73 | ||
FUNCTION STUDIES | Normal | ||
STABILITY | Hb X is less stable than Hb A and Hb S | ||
OCCURRENCE | Found in several (10-15) Black families | ||
OTHER INFORMATION | Quantity in the heterozygote 40-44%; sickling when deoxygenated; when found together with Hb S the condition resembles sickle cell anemia; insoluble in concentrated phosphate; gels at higher concentrations than Hb S; the beta73 Asp->Asn replacement is characteristic for Hb Korle- Bu |
REFERENCES | |||
1. | Bookchin, R.M., Nagel, R.L., and Ranney, H.M.: J. Biol. Chem., 242:248, 1967. | ||
2. | Nagel, R.L. and Bookchin, R.M.: Nature, 241:143, 1973. | ||
3. | Moo-Penn, W.F., Bechtel, K., Jue, D., Chan, M.S., Hopkins, G., Schneider, N.J., Wright, J., and Schmidt, R.M.: Blood, 46:363, 1975. |