α-Thalassemia Mutations in Gilan Province, North Iran

Abstract

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 α-globin mutations in 94 (91.3%) of these patients. Most prevalent of the 16 different α-thalassemia (α-thal) alleles was −α^3.7 (42.5%), followed by the polyadenylation signal (poly A2) (AATAAA>AATGAA) (12.4%), Hb Constant Spring [Hb CS, α142, Term→Gln (TAA>CAA in α2] (10.6%), – –^MED (8.8%), IVS-I donor site [GAG GTG AGG>GAG G– – – – –, α^{−5 nt} (−TGAGG)] (7.1%), −α^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 α1 gene mutations: α⁻⁹ (HBA1: c.−9 G>C) and α^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.

Keywords:

• α-Thalassemia (α-thal)
• Mutation
• Gilan province
• Iran