Mersin, Türkiye'de Beta Globin Gen Mutasyonlarının Değerlendirilmesi: Tek Merkezli Bir Deneyim

Year 2025, Volume: 12 Issue: 1, 27 - 33, 30.04.2025

Zuhal Mert Altıntaş , Nazan Eras

https://doi.org/10.47572/muskutd.1621921

Abstract

Beta-talasemi, β-globin zincir sentezinin eksikliği veya yokluğundan kaynaklanan otozomal resesif kalıtım gösteren, dünya çapında en yaygın tek gen hastalığıdır. Çalışmamızın amacı Mersin ilinde beta talasemi tanısı alan hastaların mutasyon tiplerini ve sıklığını değerlendirmektir. 2017-2019 yılları arasında Mersin Üniversitesi Tıp Fakültesi hastanesinde hemoglobinopati taraması yapılan 292 hastanın klinik verileri retrospektif olarak incelendi. HBB geninde mutasyon bulunan 292 hastanın %55,5'inde (n=162) beta talasemi vardı. Beta talasemili hastalarda, 4'ü anormal Hb varyantı olmak üzere 32 farklı mutasyon ve bu hastaların 22'sinde 12 farklı bileşik heterozigot β-tal mutasyonu tespit edildi. En sık görülen alel %25.2 frekansla c.93-21G>A idi. En yaygın bileşik varyasyon HBB:c.*233G>C/HBB:c.92+6T>C/A, (%27,4) idi. Türkiye'de daha önce bildirilmemiş olan HBB:c.92+5G>A mutasyonunu tespit ettik. Beta-talasemi mutasyonlarının tipleri ve sıklıkları coğrafi bölgeler arasında farklılık göstermektedir. Bu çalışmada, beta-talasemi mutasyonlarının yaygınlığını moleküler düzeyde incelemiş ve DNA dizi analizi ile tanımlanamayan mutasyonların tespit oranını artırmıştır. Beta-talasemide yeni mutasyonların tanımlanması genetik danışmanlık, prenatal tanı, tarama programları ve literatür için yararlıdır.

Keywords

Beta-talasemi, HBB geni, Mersin, Mutasyon, Türkiye

Evaluation of Beta Globin Gene Mutations in Mersin, Turkey: A Single Center Experience

Abstract

Beta-thalassemia is the most common single gene disease worldwide with an autosomal recessive inheritance caused by the deficiency or absence of β-globin chain synthesis. The aim of our study is to evaluate the types and frequencies of mutations in patients diagnosed with beta thalassemia in the province of Mersin. Clinical data of 292 patients who underwent hemoglobinopathy screening at Mersin University Faculty of Medicine Hospital between 2017 and 2019 were retrospectively analysed. Of the 292 patients with mutations in the HBB gene, 55.5% (n=162) had beta thalassemia. In patients with beta thalassemia, 32 different mutations, including 4 abnormal Hb variants, and 12 different compound heterozygous β-tal mutations were detected in 22 of these patients. The most commonly seen allele was c.93-21G>A with a frequency of 25.2%. The most common compound variation was HBB:c.*233G>C/HBB:c.92+6T>C/A, (27.4%). We detected the mutation HBB:c.92+5G>A, which has not been previously reported in Turkey. The types and frequencies of beta-thalassemia mutations vary among geographic regions. This study examined the prevalence of beta-thalassemia mutations at the molecular level and enhanced the detection rate of unidentified mutations by DNA sequence analysis. Identification of new mutations in beta-thalassemia is useful for genetic counseling, prenatal diagnostic, screening programs, and literature.

Keywords

Beta-thalassemia, HBB gene, Mersin, Mutation, Turkey

Ethical Statement

Mersin University Local Ethics Committee/650/2022.

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