Interaction of the α2 polyadenylation signal mutation (AATAAA → AATA- -) and α0-thalassemia (- - SEA), resulting in Hb H disease in a Thai patient

We report a Thai boy with a compound heterozygosity for the alpha2 polyadenylation signal mutation (AATAAA --> AATA- -) and alpha(0)-thalassemia (- -(SEA)), who suffered from fib If disease with more severe clinical symptoms than those usually observed with deletional fib 11 disease. His Hb H level was as high as 52% of total hemoglobin. The hematologic data of this unusual case of fib 11 disease was compared with those of Hb H disease with a homozygosity for the alpha2 polyadenylation signal mutation, and compound heterozygosity of the alpha2 polyadenylation signal mutation and alpha(0)-thalassemia. A simple DNA assay based on an allele specific polymerase chain reaction for the detection of this polyadenylation signal mutation is described.