Luísa Romão

Human α-globin gene expression is silenced by terminal truncation of chromosome 16p beginning immediately 3′ of the ζ-globin gene

SummaryThe high level expression of the human α globin genes in erythroid tissue appears to require a set of DNaseI hypersensitive sites located upstream of the human α-globin gene cluster. These sequences, termed the locus control region (LCR), include two erythroid specific and a number of less restricted DNaseI hypersensitive sites. In this report we describe an individual with α-thalassemia associated with a truncation of the short arm of chromosome 16 that removes the LCR region and inactivates the adjacent intact α-globin genes. This genetic study supports the critical role of the LCR in the transcriptional activation of the human α-globin gene cluster and substantiates the importance of LCR deletions in the etiology of α-thalassemia.