α-Thalassemia Caused by a 16 BP Deletion in the 3' Untranslated Region of the α2-Globin Gene Including the First Nucleotide of the Poly a Signal Sequence

We have identified a 16 bp deletion in the 3 untranslated region of the α2-globin gene, including the first nucleotide of the polyadenylation signal sequence. The propositus, her mother and one of her brothers, all heterozy-gotes for the above deletion, have mild microcytic anemia. This is the first description of a deletion in the a gene involving both the 3' untranslated region and the polyadenylation signal sequence, causing α-thalassemia.