Nörofibromatozis tip 1’li hastada sağ amelia

Nörofibromatozis tip 1 (NF1); deri, periferal ve santral sinir sistemi (SSS) yanında kemik, endokrin, gastrointestinal sistem gibi bir çok değişik sistemi etkiler. Otozomal dominant geçişli olup görülme sıklığı 1/3000-1/4000 olarak saptanmıştır. NF-1 geni 17. kromozom 11p12 bölgesindedir, bu gen nörofibromin olarak adlandırılan tümor supresor bir proteini kodlamaktadır. NF1 geni, nörofibromin proteini kodlar, çok çeşitli hücre ve doku tiplerinde eksprese edilir. Nörofibromin, bir GTPaz aktive edici protein (Ras-GAP) olarak işlev görerek hücre içi bir sinyal molekülü p21ras’ın (Ras) aktivitesini negatif olarak düzenler. Nörofibrominin Ras-GAP fonksiyonu, NF1 ile ilişkili çeşitli klinik semptomlarla ilişkilendirilmiştir. Bu yazıda Nörofibramatozis tip 1 klinik ve genetik olarak tanısı konulan ve sağ elde gelişimsel anomalisi (sağ el amelia) olan bir vakayı sunmayı hedefledik. Bu iki durum birlikteliğinin koinsidental mi olduğu yada nörofibramatozis sonucu mu olduğu konusunda bilgilerimiz yetersiz kalmaktadır. Amelia ve nörofibramatozis birlikteliği bir ilk olduğu için bu vakayı sunmak istedik.

Anahtar Kelimeler:

Nörofibromatozis Tip 1, Amelia, Nörofibromin

Right amelia in a patient with neurofibromatosis type 1

Neurofibromatosis type 1 (NF1) affects many different systems such as the skeletal, endocrine, gas-trointestinal systems, as well as the skin, peripheral and central nervous systems (CNS). The NF-1 gene, located in the 11p12 region of chromosome 17, encodes a tumor suppressor protein, called neurofibromin, and is expressed in a diverse range of cell and tissue types. Neurofibromin negatively regulates the activity of an intracellular signaling molecule, p21ras (Ras), acting as a GTPase-activating protein (Ras-GAP). The Ras-GAP function of neurofibromin has been associated with various NF1-related clinical symptoms. We aimed to present a case of clinically and genetically diagnosed neurofibromatosis type 1 with a developmental anomaly in the right hand (right hand amelia). Our knowledge about whether the coexistence of these two conditions is coincidental or a result of neurofibromatosis is limited. We wanted to present this case since the coexistence of amelia and neurofibromatosis is a first.

Keywords:

Neurofibromatosis type 1, Amelia, Neurofibromin,

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