Regulation of human alpha-globin gene expression and alpha-thalassemia.

Departamento de Patologia Clínica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, SP, Brasil.
Genetics and molecular research: GMR (Impact Factor: 0.85). 02/2008; 7(4):1045-53. DOI: 10.4238/vol7-4gmr472
Source: PubMed

ABSTRACT Hemoglobin and globin genes are important models for studying protein and gene structure, function and regulation. We reviewed the main aspects of regulation of human alpha-globin synthesis, encoded by two adjacent genes (alpha(2) and alpha(1)) clustered on chromosome 16. Their expression is controlled mainly by a regulatory element located 40 kb upstream on the same chromosome, the alpha-major regulatory element, whose activity is restricted to a core fragment of 350 bp, within which several regulatory protein binding sites have been found. Natural deletions involving alpha-major regulatory element constitute a particular category of alpha-thalassemia determinants in which the alpha-globin genes are physically intact but functionally inactive.

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