MUTATION | Codons 128/129 (-4 bp, -GCTG; +5 bp, +CCACA) Codons 132-135 (-11 bp, -AAAGTGGTGGC) | ||
---|---|---|---|
AMINO ACID REPLACEMENT | None | ||
TYPE OF BETA-THAL | Dominant inclusion body beta-thal trait | ||
MECHANISM | This complex rearrangement results in the synthesis of a betaX chain with 153 residues which is unstable and catabolized, resulting in this TYPE OF BETA-THAL | ||
IDENTIFICATION | Cloning of the beta-globin gene; DNA sequencing | ||
HEMATOLOGY IN HETEROZYGOTE(S) | Moderate anemia with splenomegaly; levels of Hb F and Hb A2 are increased; decreased beta/alpha chain synthesis ratio; some subjects were splenectomized | ||
HEMATOLOGY IN HOMOZYGOTE(S) | None | ||
OCCURRENCE | In an Irish family; eight affected members | ||
HAPLOTYPE | [+ - - - - + +] | ||
FOUND IN COMBINATION WITH ABNORMAL HB(S) | None | ||
FOUND IN COMBINATION WITH BETA-THAL ALLELE(S) | None | ||
OTHER INFORMATION | No abnormal beta chain could be isolated |
REFERENCES | |||
1. | Weatherall, D.J., Clegg, J.B., Knox-Macaulay, H.H., Bunch, C., Hopkins, C.R., and Temperley, I.G.: Br. J. Haematol., 24:681, 1973. | ||
2. | Thein, S.L., Hesketh, C., Taylor, P., Temperley, I.J., Hutchinson, R.M., Old, J.M., Wood, W.G., Clegg, J.B., and Weatherall, D.J.: Proc. Natl. Acad. Sci. USA, 87:3924, 1990. |