Hematological phenotype of the IVS-I-5 (G > C) beta-thalassemia mutation and assessment of Iran's national screening criteria.

In a recent study, we demonstrated that, in the Iranian province of Sistan-Baluchestan (S-B), the IVS-I-5 (G > C) beta-thalassemia (beta-thal) mutation is highly prevalent. In the present article we report the hematological phenotype as measured in 289 carriers of this mutation. We evaluate the use of MCV and MCH parameters as proposed in Iran's national screening guidelines for use in this province. The Hb A(2) cut off of 3.5%, also recommended in the national guidelines, gave 2.7% false negative, as is to be expected due to coexisting elements such as measurement artefacts and delta-thal.