|
|
|
|
MUTATION | |
Codon 47 (+A); GAT(Asp)->GAA(Glu)·T | |
|
AMINO ACID REPLACEMENT | |
See above | |
TYPE OF BETA-THAL | |
beta° | |
MECHANISM | |
The insertion of an extra A in codon 47 introduces a frameshift with a stop codon at codon 52 (TGA) and termination of translation | |
IDENTIFICATION | |
Amplification of the beta-globin gene; DNA sequencing; dot-blot analysis with allele specific oligonucleotide probes; ASO | |
HEMATOLOGY IN HETEROZYGOTE(S) | |
Found in 14 members of a family from Surinam: Hb 9.4-12.1 g/dl; MCV 68-85 fl; anisopoikilocytosis, microcytosis, target cells; Hb A2+Hb B2 3.5-4.5%; Hb F <1.0% | |
HEMATOLOGY IN HOMOZYGOTE(S) | |
Not observed | |
OCCURRENCE | |
In only one family from Surinam | |
HAPLOTYPE | |
Unknown | |
FOUND IN COMBINATION WITH ABNORMAL HB(S) | |
Not observed | |
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S) | |
Not observed | |
OTHER INFORMATION | |
The mutation occurs together with a delta chain variant (codon 16, G->C) on the same chromosome (linkage of Hb B2 and beta-thal) (Ref. 1) | |
|
|
|
|
REFERENCES |
1. | |
Huisman, T.H.J., Punt, K., and Schaad, J.D.G.: Blood, 17:747, 1961. | |
2. | |
Codrington, J.F., Li, H-W., Kutlar, F., Gu, L-H., Ramachandran, M., and Huisman, T.H.J.: Blood, 76:1246, 1990. | |
3. | |
Losekoot, M., Fodde, R., van Heeren, H., Harteveld, C.L., Giordano, P.C., and Bernini, L.F.: Hemoglobin, 14:467, 1990. | |