ÖZ
Amaç
İskelet displazisi, iskelet sisteminin gelişimini etkileyen heterojen hastalık gurubudur. Kompleks doğası nedeniyle, klinik ya da radyolojik değerlendirmeler bilgi verici olabilir; ancak moleküler yaklaşımlar ayırıcı tanı ve alt tiplerin belirlenmesi açısından daha etkilidir. Kohort çalışmaları ilişkili genleri ve varyantları aydınlatmış olsa da bu konuda halen çalışmaya ihtiyaç duyulmaktadır. Sunulan çalışma bir Türk kohortunda genotip-fenotip ilişkisini araştırmayı amaçlamaktadır.
Yöntemler
Sunulan çalışmaya 36 hasta dahil edilmiştir. Hastalar, Genetik İskelet Hastalıklarının Nozolojisi, 2023’e göre gruplandırılmıştır. Genetik tanı algoritmasına uygun olarak hastalara Sanger dizileme, hedefli gen paneli, klinik ekzom dizileme ya da tüm ekzom dizileme çalışılmıştır. Tespit edilen spesifik varyantlar için mevcut literatür derlenmiştir.
Bulgular
Katılımcılar arasında kadın sayısı (%63,9), erken sayısından (%36,1) daha fazladır. Kritik olarak, 16 hastanın (%45,7) ebeveynleri akrabadır. Otuz altı hastanın 29’unda patojenik ya da olası patojenik varyant tespit edilmiştir. Dizileme metoduna bağlı olarak tanı verimi %80’dir. Nozolojiye göre moleküler tanısı en yüksek olan gruplar, grup 2, tip II kolajen hastalıkları (5 hastada COL2A1 varyantları) ve grup 34, kraniosinostozlu sendromlar (5 hastada FGFR2, FGFR3, TWIST1 ya da SMO varyantları) şeklindedir.
Sonuç
Sunulan çalışma, bir Türk kohortunda, iskelet displazisinde genetik ve fenotipik varyasyonları vurgulamıştır. Elde edilen bulguların mevcut literatüre katkı sunması ve hasta takibi ve değerlendirmesi açısından klinisyenleri yönlendirmesi beklenmektedir.
Anahtar Kelimeler:
İskelet displazisi, moleküler tanı, dizileme
Kaynaklar
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