A new alpha(0)-thalassemia deletion found in a Dutch family (--(AW))

• Published in: Blood cells, molecules, & diseases molecules, & diseases, 2010-08, Vol.45 (2), p.133-135
• Main Authors: Phylipsen, Marion, Vogelaar, Ingrid P, Schaap, Rianne A C, Arkesteijn, Sandra G J, Boxma, George L, van Helden, Willem C H, Wildschut, Irene C M, de Bruin-Roest, Andrea C, Giordano, Piero C, Harteveld, Cornelis L
• Format: Article
• Language: English
• Subjects: Adult; Aged, 80 and over; alpha-Globins - deficiency; alpha-Globins - genetics; alpha-Thalassemia - blood; alpha-Thalassemia - diagnosis; alpha-Thalassemia - genetics; Female; Humans; Male; Middle Aged; Netherlands; Sequence Deletion - genetics
• ISSN: 1096-0961
• DOI: 10.1016/j.bcmd.2010.05.004

Alpha-thalassemia is an inherited hemoglobin disorder characterized by a microcytic hypochromic anemia caused by a quantitative reduction of the alpha-globin chain. The majority of the alpha-thalassemias is caused by deletions in the alpha-globin gene cluster. A deletion in the alpha-globin gene cluster, which was found in a Dutch family, was characterized by MLPA, long-range PCR and direct sequencing. We describe the molecular characterization of a novel 8.2kb deletion (--(AW)), involving both alpha-globin genes in cis. The deletion is caused by a non-homologous recombination event between an Alu and an L1-repeat sequence. This deletion is the third example of a non-homologous recombination event involving an Alu and an L1 repeat, and the first described in the human alpha-globin gene cluster. Because of a 25% risk of Hb Bart's with hydrops foetalis in the offspring when in combination with another alpha(0)-thalassemia allele, it is important to diagnose this deletion.