Molecular characterization of alpha-Thalassemia in Adana, Turkey: A single center study

alpha-Thalassemia (alpha-thal) is a widespread genetic disorder throughout the world caused primarily by reduced synthesis of the alpha-globin chains, and it has been found at a high incidence in Turkey. Our aim in this study was to determine the frequency and molecular properties of alpha-thal in Adana, Turkey.

A total of 3,000 individuals comprising premarital couples or patients with anemia were screened between 2007 and 2008. Hematological parameters were analyzed using an automatic cell counter, and to detect the carriers of hemoglobin variants, high-performance liquid chromatography was used. Molecular screening of the alpha-globin gene was carried out by an Alpha-Globin StripAssay which is based on multiplex PCR for specific amplification.

We have identified 225 cases with alpha-thal and found that the prevalence of alpha-thal is 7.5% in this area. In molecular analyses, the alpha-thal gene mutations alpha(3.7), alpha(4.2), --(MED), --(20.5), alpha(PA-2)alpha, alphaalphaalpha(anti-3.7), and alpha(PA-1)alpha were detected.

Our results showed that the alpha-thal mutations represent a great heterogeneity and that the -alpha(3.7) deletion has the highest frequency in Adana.