β‐thalassemia alleles and unstable hemoglobin types among russian pediatric patients

A recently initiated collaboration between Russian and American institutions has resulted in the characterization of several known or new β‐thalassemia alleles and unstable hemoglobin types. Nine known β‐thalassemia alleles were present which have also been found in Mediterranean, East Asian, and Black populations; the possibility of independent mutations for some of the rare alleles should be considered. Hb Durham‐N.C./Brescia with a codon 114 (CTG → CCG; Leu → Pro) change was present in six members of two families. This condition and two new variants have the characteristics of a dominant type of β‐thalassemia heterozygosity with moderate anemia, Heinz body formation, splenomegaly, etc. One new β‐thalassemia allele is a frame‐shift at codon 124 (‐A), while another is characterized by the introduction of an extra proline residue (codon: CCA) between residues Thr (β123) and Val (β126) to give the sequence ‐Thr‐Pro‐Pro‐Pro‐Val‐. © 1994 Wiley‐Liss, Inc.