RESUMO
One hundred and three patients from Gilan Province, Iran, presenting with hypochromic and microcytic anemia parameters without iron deficiency were included in this study. Using gap-polymerase chain reaction (gap-PCR), reverse hybridization StripAssay and DNA sequencing, we detected a total of 113 alpha-globin mutations in 94 (91.3%) of these patients. Most prevalent of the 16 different alpha-thalassemia (alpha-thal) alleles was -alpha(3.7) (42.5%), followed by the polyadenylation signal (poly A2) (AATAAA>AATGAA) (12.4%), Hb Constant Spring [Hb CS, alpha142, Term-->Gln (TAA>CAA in alpha2] (10.6%), --(MED) (8.8%), IVS-I donor site [GAG GTG AGG>GAG G-----, alpha(-5 nt) (-TGAGG)] (7.1%), -alpha(4.2) (4.4%) and poly A1 (AATAAA>AATAAG) (3.5%). An additional nine mutations were observed at frequencies below 2%. We also found two novel alpha1 gene mutations: alpha(-9) (HBA1: c.-9 G>C) and alpha(IVS-I-4) (HBA1: c.95+4 A>G). Our new findings will be valuable for improving targeted thalassemia screening and prevention strategies in this area.