First report on the co-inheritance of (beta) IVS I-1 (G-->T) Thalassemia with the (gamma) CD85 [Phe-->Ser (F1) (TTT-->TCT)] HbA2 Etolia in Iran

Medical Genetics Laboratory of Dr. Zeinali, Tehran, Iran. zeinali@medicalgeneticslab.com

Beta thalassemia minor phenotypes with normal HbA2 levels and decreased MCV and MCH values are relatively rare beta-thalassemia traits. Here, we describe a case with normal HbA2 and decreased MCV and MCH level. Amplification refractory mutation system-polymerase chain reaction(ARMS-PCR) revealed IVS I-1 (G-->T) mutation in the beta-globin gene. Direct sequencing of the delta-globin gene revealed a previously reported Hb variant called Hb A2 Etolia (Gene Bank Accession No. DQ106871). This is the first case reporting HbA2 Etolia in association with the beta-IVS I-1 (G-->T) mutation in Iran. Reduced HbA2 expression by a co-inherited HbA2 variant resulting in decreased HbA2, in Cis or Trans, may cause problems in carrier diagnostics and eventually in genetic counseling and prenatal diagnosis when insufficient molecular analyses are performed.