Türkiye'nin Doğu Anadolu Bölgesindeki Meme Kanseri Hastalarında BRCA1-BRCA2 Gen Varyasyonlarının Araştırılması: Genetik Yatkınlık ve Klinik Sonuçlar Üzerine Bir Çalışma

Öz

Amaç: Bu çalışmanın amacı Doğu Anadolu Bölgesi'ndeki meme kanserli hastalarda BRCA1 ve BRCA2 gen varyasyonlarını araştırmak ve bu varyasyonların hastaların genetik yatkınlığı ve klinik sonuçları üzerindeki etkilerini değerlendirmektir. Gereç ve Yöntemler: Çalışma, 2020-2023 yılları arasında meme kanseri tanısı almış veya ailesinde birden fazla meme kanseri vakası öyküsü olan 146 kadın üzerinde yürütülmüştür. Katılımcılardan genomik DNA izole edilmiş ve BRCA1/2 genlerinin tamamı dizilenmiştir. Veriler istatistiksel olarak analiz edilmiştir. Sonuçlar: Çalışmada BRCA genlerinde 17 farklı genetik varyasyon tespit edilmiştir. Bu varyasyonlardan dördü patojenik olarak sınıflandırılmış, potansiyel olarak protein yapısında önemli değişikliklere neden olmuş ve kanser riskini artırmıştır. Buna ek olarak, bazı varyasyonlar, sağlık üzerindeki etkileri belirsizliğini koruyan Belirsiz Öneme Sahip Varyantlar (VUS) olarak sınıflandırılmıştır. Sonuç: Bu çalışma, Doğu Anadolu bölgesindeki meme kanseri hastalarında BRCA1 ve BRCA2 gen varyasyonlarını araştırarak genetik yatkınlık ve kanser gelişimi arasındaki ilişkiyi aydınlatmaktadır. BRCA genlerinde kanser riskini artırma potansiyeline sahip dört patojenik varyasyon tanımlanmıştır. Buna ek olarak, 12 varyasyon VUS olarak sınıflandırılmıştır ve bunların sağlık üzerindeki etkileri henüz belirlenmemiştir. Bulgularımız genetik danışmanlık ve hastalık yönetimi için önemli bilgiler sunmakta ve hastalar için kişiselleştirilmiş tedavi yaklaşımlarının geliştirilmesine olanak sağlamaktadır.

Anahtar Kelimeler

• BRCA1
• BRCA2
• Meme Kanseri
• Genetik Varyasyon
• Doğu Anadolu Bölgesi

Investigation of BRCA1-BRCA2 Gene Variations in Breast Cancer Patients in the Eastern Anatolian Region of Turkey: A Study of Genetic Predisposition and Clinical Outcomes

Abstract

Objective: This study aims to investigate BRCA1 and BRCA2 gene variations in breast cancer patients in Eastern Anatolia region and to evaluate the effects of these variations on patients' genetic predisposition and clinical outcome. Materials and Methods: The study was conducted on 146 women diagnosed with breast cancer or with a family history of multiple breast cancer cases between 2020 and 2023. Genomic DNA was isolated from the participants and the entire BRCA1/2 genes were sequenced. The data were statistically analysed. Results: The study identified 17 different genetic variations in the BRCA genes. Four of these variations were classified as pathogenic, potentially causing significant changes in protein structure and increasing the risk of cancer. In addition, some variations were classified as Variants of Uncertain Significance (VUS), whose health effects remain unclear. Conclusion: This study elucidates the relationship between genetic predisposition and cancer development by investigating BRCA1 and BRCA2 gene variations in breast cancer patients in the Eastern Anatolian region. Four pathogenic variations in the BRCA genes were identified that have the potential to increase cancer risk. In addition, 12 variations were classified as VUS and their health effects have yet to be determined. Our findings provide important information for genetic counselling and disease management, enabling the development of personalised treatment approaches for patients.

Keywords

• BRCA1
• BRCA2
• Breast Cancer
• Genetic Variation
• Eastern Anatolia Region

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