Association of Vitamin D Receptor Variants with Epilepsy in a Turkish Population

Öz

Objective: Evidence regarding the relationship between vitamin D receptor (VDR) polymorphisms and epilepsy remains limited in many populations. This study evaluated the possible contribution of VDR gene variants to epilepsy susceptibility in a Turkish cohort. Methods: A total of 67 individuals diagnosed with epilepsy and 122 neurologically healthy participants were enrolled in the study. Genotyping of the VDR BsmI (rs1544410), ApaI (rs7975232), and TaqI (rs731236) polymorphisms was performed using the MassARRAY iPLEX GOLD system. Genotype distributions, Hardy–Weinberg equilibrium status, haplotype structures, linkage disequilibrium patterns, and clinical associations were analyzed statistically. Results: BsmI and TaqI genotype distributions differed between groups (p=0.024 and p<0.001), whereas ApaI showed no significant difference (p=0.072). The TaqI GG genotype was associated with higher epilepsy risk (OR=78.44, 95% CI: 4.38–1403.52, p=0.003). Hardy–Weinberg deviation was observed for ApaI in both groups and for BsmI and TaqI in controls after Bonferroni correction. The CCA haplotype was more common in controls (24.59% vs. 14.18%, p=0.018), while the CAG haplotype was enriched in epilepsy patients (3.84% vs. 0.45%, p=0.023). The strongest linkage disequilibrium was identified between BsmI and TaqI (D’=0.907, r²=0.739). Conclusion: Distinct VDR genetic patterns were identified in epilepsy patients compared with healthy controls in this Turkish cohort.

Anahtar Kelimeler

• Epilepsy
• Vitamin D Receptor
• Polymorphism
• Haplotypes
• Genetic Susceptibility.

Etik Beyan

The study protocol was reviewed and approved by the Ethics Committee of Kafkas University Faculty of Medicine (06/10.07.2015).

Teşekkür

We would like to thank Prof. Dr. Nergiz Hüseyinoğlu for her support of this study.

Türk Popülasyonunda D Vitamini Reseptör Varyantlarının Epilepsiyle İlişkisi

Öz

Amaç: Birçok popülasyonda D vitamini reseptörü (VDR) polimorfizmleri ile epilepsi arasındaki ilişkiye dair kanıtlar hâlâ sınırlıdır. Bu çalışma, Türk kohortunda VDR gen varyantlarının epilepsiye yatkınlığa olası katkısını değerlendirmiştir. Yöntemler: Çalışmaya epilepsi tanısı konmuş toplam 67 kişi ve nörolojik açıdan sağlıklı 122 katılımcı dahil edilmiştir. VDR BsmI (rs1544410), ApaI (rs7975232) ve TaqI (rs731236) polimorfizmlerinin genotiplemesi, MassARRAY iPLEX GOLD sistemi kullanılarak gerçekleştirilmiştir. Genotip dağılımları, Hardy–Weinberg dengesi durumu, haplotip yapıları, bağlantı dengesizliği modelleri ve klinik ilişkiler istatistiksel olarak analiz edilmiştir. Bulgular: BsmI ve TaqI genotip dağılımları gruplar arasında farklılık gösterirken (p=0,024 ve p<0,001), ApaI'de anlamlı bir fark görülmedi (p=0,072). TaqI GG genotipi, daha yüksek epilepsi riski ile ilişkiliydi (OR=78,44, %95 CI: 4,38–1403,52, p=0,003). Bonferroni düzeltmesinden sonra, her iki grupta ApaI için ve kontrol grubunda BsmI ve TaqI için Hardy–Weinberg sapması gözlendi. CCA haplotipi kontrol grubunda daha yaygındı (%24,59’a karşı %14,18, p=0,018), CAG haplotipi epilepsi hastalarında daha yaygındı (%3,84’e karşı %0,45, p=0,023). En güçlü bağlantı dengesizliği BsmI ve TaqI arasında tespit edildi (D’=0,907, r²=0,739). Sonuç: Bu Türk kohortunda, kontrollere kıyasla epilepsi hastalarında farklı VDR genetik kalıpları tespit edildi. .

Anahtar Kelimeler

• Epilepsi
• D vitamini reseptörü
• polimorfizm
• haplotipler
• genetik yatkınlık.

Etik Beyan

Çalışma protokolü, Kafkas Üniversitesi Tıp Fakültesi Etik Kurulu tarafından incelenmiş ve onaylanmıştır (06/10.07.2015).

Teşekkür

Çalışmaya destek verdiği için Prof. Dr. Nergiz Hüseyinoğlu'na teşekkür ederiz.

Kaynakça

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