Mutation Analysis of Beta-Thalassemia Major Patients and Their Parents in Diyarbakir Province, Turkey

Objectives: In this study, beta-Thalassemia Major (BTM) diagnosed patients and their parents were subjected to DNA sequencing in order to confirm their diagnosis, improve their treatment and determine the mutation distributions of both patients and their parents. Methods: A total of 90 people, BTM patients (n=30) and their parents (n=60), were included in the study. For all analyses, two blood samples were taken into EDTA-containing tubes from each of the patients and each of their parents. Complete blood count, hb variant and mutation analysis were studied, respectively. Results: 8 types of mutation were determined: IVS-I-110 (G->A) 46.67%, codon 8 (-AA) 16.67%, IVS-II-1 (G->A) 11.67%, codon 44 (-C) 10.00%, IVS-II-745 (C->G) 5.00%, IVS-I-1 (G->A) 3.33%, IVS-I-5 (G->T) 3.33% and -30 (T- >A) 3.33%. Hb concentrations of 9.2 ± 1.32 g/dL and Hb variant levels of HbA 81.58% ± 11.05, HbF 10.44% ± 11.54 were found in patients with BTM who received transfusion therapy regularly. Typical hemogram count and Hb variants levels were seen in parents. Conclusion: In our study, a similar distribution was identified throughout Turkey in terms of mutation. Mutations were classified in all the studied people. This study increased the detection percentage of undetermined mutations by the use of DNA sequencing. Thus a multi-centric coordinated study with high capacity will improve detecting these mutations and their effects on the disease.

Diyarbakır İlinde Beta-Talasemi Majörlü Hastalar ve Ebeveynlerinde Mutasyon Analizi

Amaç: Bu çalışmada beta-Talasemi Majör (BTM) tanısı almış hastalar ve ebeveynlerinde; DNA dizi analizi yöntemiyle tanısının kesinleştirilmesi, tedavisine katkıda bulunulması ve mutasyon dağılımının tespiti amaçlanmıştır. Yöntemler: Çalışmaya BTM’li hastalar (n=30) ve ebeveynleri (n=60) olmak üzere toplam 90 kişi dâhil edilmiştir. Tüm analizler için hastalar ve ebeveynlerinin her birinden iki adet EDTA ihtiva eden tüplere kan numunesi alınmıştır. Sırasıyla tam kan sayımı, Hb varyant ve mutasyon analizi çalışılmıştır. Bulgular: IVS-I-110 (G->A) %46.67, codon 8 (-AA) %16.67, IVS-II-1 (G->A) %11.67, codon 44 (-C) %10.00, IVS-II745 (C->G) %5.00, IVS-I-1 (G->A) %3.33, IVS-I-5 (G->T) %3.33 ve -30 (T->A) %3.33 olmak üzere 8 çeşit mutasyon tespit edildi. Düzenli olarak transfüzyon tedavisi alan BTM’li hastalarda Hb konsantrasyonu 9.2±1.32 g/dL ve Hb varyant düzeyi HbA %81.58±11.05, HbF %10.44±11.54 olarak tespit edilmiştir. Ebeveynlerde ise tipik hemogram sayımı ve Hb varyant düzeyleri görüldü. Sonuç: Çalışmamızda mutasyon açısından Türkiye geneline benzer bir dağılım tespit edildi. Çalışılan tüm kişilerde mutasyonlar tasnif edildi. Bu çalışma DNA dizi analizi yönteminin kullanımına bağlı olarak saptanamayan mutasyonların belirlenme oranını artırmıştır. Buna bağlı olarak yüksek kapasiteli çok merkezli koordine bir çalışma ile bu mutasyonların ve bunların hastalığa etkisinin belirlenmesini geliştirecektir.

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