B12 Vitamini Eksikliği Olan Çocuklarda DNA Hasarı Göstergesi;8-hidroksi-2′-deoksiguanosin (8-OHdG)

Öz

Amaç: B12 vitamini, insan organizmasının sentezleyemediği bir vitamindir. DNA ve miyelin sentezinde esasen gereklidir. Çalışmamızda, B12 vitamini eksikliği olan çocuklarda DNA hasarının bir göstergesi olarak 8-OHdG düzeyini değerlendirerek B12 eksikliğinin DNA hasarıyla ilişkisini belirlemeyi amaçladık. Materyal ve metod: Çalışmaya, B12 vitamini eksikliği tanısı konmuş 0-18 yaş arası toplam 44 hasta ve aynı yaş grubundaki 40 sağlıklı çocuk kontrol grubu olarak dahil edildi. DNA hasarı göstergesi olarak 8-OHdG düzeyleri, idrar ve serum örneklerinde enzim immünolojik test kiti ile ölçüldü.
Bulgular: B12 vitamini eksikliği olan 44 hastanın serumunda 8-OHdG düzeyi 13,99±6,27 ng/ml, idrarında ise 71,48±70,5 ng/ml olarak bulunmuştur. Sağlıklı kontrol grubunda ise ortalama değerler serumda 9,61±5,82 ng/ml, idrarda ise 19,18±12,59 ng/ml olarak tespit edilmiştir.
Sonuç: B12 vitamini eksikliği olan çocuklarda serum ve idrarda oksidatif stres ve DNA hasarı göstergesi olarak 8-OHdG düzeyinin arttığı ve B12 vitamini eksikliğinin DNA hasarına neden olduğu belirlenmiştir.

Anahtar Kelimeler

• Çocuklar
• B12 vitamini eksikliği
• DNA hasarı
• 8-hidroksi-2'-deoksiguanosin
• Oksidatif stres

Destekleyen Kurum

Harran Üniversitesi Araştırma Fonu

Proje Numarası

Harran Üniversitesi Araştırma Fonu Saymanlığı tarafından 27/10/2017 tarih ve 17195 proje numarası ile desteklenmiştir.

Etik Beyan

Ethical approval for this study was obtained from the by Harran University Faculty of Medicine Clinical Research Ethics Committee (approval no: E.26524, date: July, 13, 2017).

Teşekkür

16 Nisan 2026 Sayın Editör, ''B12 Vitamini Eksikliği Olan Çocuklarda DNA Hasarı Göstergesi; 8-hidroksi-2′-deoksiguanosin (8-OHdG)'' başlıklı makalemizi yayınlanmak üzere değerlendirmeniz için derginize sunuyoruz. Klinik çalışma, Kurumsal Etik Kurul onayı sonrasında gerçekleştirilmiş olup, tüm katılımcılar yazılı bilgilendirilmiş onam vermiş ve tüm imzalı onam formlarını toplamış bulunmaktayız. Bu raporun özgün olduğunu ve makalenin tamamının veya bir kısmının ya da yakından ilgili diğer makalelerin (özet veya tez biçimi dışında) daha önce yayınlanmadığını veya başka bir dergi tarafından yayınlanmak üzere değerlendirilmediğini onaylıyoruz. Kabul edilmesi halinde, makale, telif hakkı sahibinin yazılı izni olmadan, aynı biçimde, İngilizce veya başka bir dilde başka bir yerde yayınlanmayacaktır. Açıklanan çalışmaya doğrudan katkıda bulunan tüm yazarlar, makaleyi okumuş ve Harran Üniversitesi Tıp Fakültesi Dergisi'ne gönderilmesini onaylamıştır. Sunulan makaleyle ilgili veya ilgisiz olarak çıkar çatışmasına yol açabilecek herhangi bir ticari ilişkimiz, sözleşmesel bağımız veya mülkiyet hususumuz bulunmamaktadır ve bildirilen çalışmada veya belirtilen sonuçlarda, çıkarımlarda veya görüşlerde önyargı sorusunu gündeme getirebilecek herhangi bir katılım olmamıştır. Bu makaleyi değerlendirdiğiniz için teşekkür ederiz. Saygılarımla,

DNA Damage Indicator in Children with Vitamin B12 Deficiency;8-hydroxy-2′-deoxyguanosine (8-OHdG)

Öz

Background: Vitamin B12 is a vitamin that human organism cannot synthesize. It is essentially necessary in the synthesis of DNA and myelin. This study aimed to determine the association between B12 deficiency and DNA damage by evaluating 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels as an indicator of DNA damage in children with vitamin B12 deficiency.
Materials and Methods: A total of 44 patients aged between 0-18 years old who diagnosed with vitamin B12 deficiency and a total of 40 healthy children in the same age group as control group were included in the study. 8-OHdG levels, as a DNA damage indicator, were measured using an enzyme immunoassay kit in urine and serum samples.
Results: The mean 8-OHdG level of 44 patients with vitamin B 12 deficiency was found to be 13.99±6.27 ng/ml in the serum and 71.48±70.5 ng/ml in the urine, whereas the mean values in the healthy control group were 9.61±5.82 ng/ml in the serum and 19.18±12.59 ng/ml in the urine.
Conclusions: It was determined that oxidative stress and 8-OHdG level as DNA damage indicator increased in the serum and urine in children with vitamin B12 deficiency, and vitamin B12 deficiency caused DNA damage.

Anahtar Kelimeler

• Children
• Vitamin B12 deficiency
• DNA damage
• 8-hydroxy-2' –deoxyguanosine
• Oxidative stress

Destekleyen Kurum

Harran University Research Fund

Proje Numarası

Harran Üniversitesi Araştırma Fonu Saymanlığı tarafından 27/10/2017 tarih ve 17195 proje numarası ile desteklenmiştir.

Etik Beyan

Ethical approval for this study was obtained from the by Harran University Faculty of Medicine Clinical Research Ethics Committee (approval no: E.26524, date: July, 13, 2017).

Teşekkür

April 16, 2026 Dear Editor, We are submitting our article entitled "8-hydroxy-2′-deoxyguanosine (8-OHdG) as an Indicator of DNA Damage in Children with Vitamin B12 Deficiency" to your journal for your consideration. The clinical study was conducted after approval by the Institutional Ethics Committee, and all participants provided written informed consent, and we have collected all signed consent forms. We confirm that this report is original and that neither the entire article nor any part thereof, nor any closely related articles (except in abstract or dissertation form), has been previously published or considered for publication by another journal. If accepted, the article will not be published elsewhere in the same form, in English or any other language, without the written permission of the copyright holder. All authors who directly contributed to the described study have read the article and approved its submission to the Harran University Faculty of Medicine Journal. We have no commercial associations, contractual relations, or proprietary considerations that might pose a conflict of interest related or unrelated with the submitted manuscript, and have had no involvements that might raise the question of bias in the work reported or in the conclusions, implications, or opinions stated. Thank you for evaluating this article. Sincerely,

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