بررسی پراکندگی موتاسیون های آلفا تالاسمی در مزدوجین مشکوک نهایی شهرستان بابلسر 1385 -91

Background and purpose: Alpha thalassemia is one of the most common hemoglobin disorders. Some combination of alpha globin gene mutations may cause HbH disease with severe anemia or intermediate thalassemia. In this study we aimed to determine the spectrum of alpha globin gene mutations especially rare mutation at alpha carrier couples in Babolsar, north of Iran. Discovering this spectrum is of great importance in perinatal diagnosis of alpha thalassemia and prevention of HbH disease in newborn and pregnancies affected by hydrops fetalis. Materials and methods: This descriptive study was carried out in 2006-2011. The research population included 242 suspected carriers of alpha thalassemia (110 female and 130 male) with hypocrom and microcytic anemia (MCV <80, and MCH <27) and hgb-electrophoresis (including HgbA2 <3.5), normal ferritin, TIBC, iron serum level, and resistant to iron therapy who were referred to genetics center for determination of alpha thalassemia, silent beta thalassemia, delta-beta thalassemia, or alphabeta thalassemia. The type of mutation and frequency indices were also determined. Results: Among the subjects there were two individuals with alpha-beta thalassemia. Alpha mutations was detectable in 205 (85.3%) and not detectable in 35 cases (14.7%). We found 77.5% with silent thalassemia, 19% with thalassemia trait, and 3.5% with HgbH and just one individual who was transfusion dependent. Conclusion: We found -α3.7 as the most common alpha globin chain mutation. Also, comparison of these results with the similar finding from other provinces showed that the distributions of mutations in the northern area are different with south or southeast of the country. In our study there were less frequencies of HbH disease dependent to transfusion. However, rare point mutations for example cd was observed more in this study.