Subtypes of alpha thalassemia diagnosed at a medical center in Jordan

AMAÇ: Bu retrospektif çalışma, Ürdün’deki bir Tıp Merkezi’ndeki bir grup hastada α-Talasemi mutasyonlarını ve HbH hastalığı genotipini analiz etmektedir. YÖNTEM: Toplam 430 kişi üzerinde çalışıldı. Hb H hastalığı elektroforez, HPLC ve HbH inklüzyon cisimciklerinin supra vital boyanması ile doğrulandı. DNA analizleri; polimeraz zincir reaksiyonu, restriksiyon enzim yöntemini takiben tanı ve şüpheli α-talasemi olgularının doğrulanması için agaroz jel elektroforezi ve ters hibridizasyon analizi kullanılarak gerçekleştirildi. BULGULAR: 430 olgunun α-talasemi taşıyıcısı olduğu tepit edildi ve bu durum polimeraz zincir reaksiyonu yöntemi ile doğrulandı, beş farklı α-talasemi alt belirleyici saptandı. Otüzüç olguya HbH hastalığı tanısı kondu. SONUÇ: Bu çalışma HbH hastalarının genotiplerini ortaya koyarak hastalığın fenotipik şiddetini tahmin etmeye destek olmaktadır. Çalışma sonuçları aynı zamanda, HbH hastalığı olan kişiler için ileriye yönelik genetik danışmanlık hizmetleri amacıyla da kullanılabilir, çünkü ileri olgularda prenatal tanı gereksinimi ortaya çıkabilmektedir.

Anahtar Kelimeler:

İmmünofenotiplendirme, Restrüksiyon haritası, Ürdün, Hemoglobin H, Elektroforez, agar jel, Geriyedönük çalışma, alfa-Talasemi, Polimeraz zincir reaksiyonu

Ürdün’de bir tıp merkezinde tanı konan alfa talasemilerin alt tipleri

BACKGROUND: This retrospective analysis study provides the molecular genetics of α-Thalassemia Mutations and identify the genotype of HbH disease in a group of patients at a Medical Center in Jordan. METHODS: A total of 430 subjects were studied. HbH disease was confirmed by Electrophoresis, HPLC and the demonstration of HbH inclusion bodies by supra vital staining. DNA analysis was performed using polymerase chain reaction, restriction enzyme digestion, followed by agarose gel electrophoresis and by reverse- hybridization assay to diagnose and confirm cases suspected α-thalassemia. RESULTS: Four hundred and thirty cases were found to be α-thalassemia trait and this was confirmed by Polymerase Chain Reaction, five different α- thalassemia determinants were observed. Thirty three cases were diagnosed as HbH disease. CONCLUSION: This study helps in the prediction of the phenotype severity by identifying the genotype of HbH patients .The results of the study can be also applied for the genetic counseling to prospective patients with HbH disease, since in severe cases the need may be arise for prenatal diagnosis in population.

Keywords:

Immunophenotyping, Restriction Mapping, Jordan, Hemoglobin H, Electrophoresis, Agar Gel, Retrospective Studies, alpha-Thalassemia, Polymerase Chain Reaction,

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