Waardenburg Sendromu'nda Tanımlanan Çok Nadir Bir PAX3 Geni Varyantı: c.232G>A(p.Val78Met)

Waardenburg Sendromu(WS); İlk olarak PJ Waardenburg tarafından tanımlanmış, deri, saç, göz veya kohleadaki stria vascularis'te melanositlerin fiziksel yokluğundan kaynaklanan hastalıktır. Poliozis (saçta beyaz perçem), hipopigmente maküller, canlı mavi gözler veya heterokromik iris ve sensörinöral işitme kaybı dahil pigmentasyon anormalliklerinin birlikteliği ile karakterizedir. Bu sendromda altı gen mutasyonu suçlanmaktadır. Bunlar; PAX3 (Paired box 3 transkripsiyon faktörün) geni, MITF (Mikroftalmi ile ilişkili transkripsiyon faktörü) geni, EDN3 (Endotelin 3) geni, EDNRB (Endotelin reseptör tip B) geni, SOX10 (Sry bOX10 transkripsiyon faktörü) geni ve SNAI2 (Snail homolog 2) genleridir. Çok nadir bir hastalıktır, prevelansı 1/42000’dir. Kadın ve erkeklerde eşit oranda görülür. Bu yazıda PAX3 geni ekzon 2’de c.232G>A(p.Val78Met) patojenik varyantı tespit edilerek Waardenburg Sendromu teşhisi konan 2 aylık nadir bir olgu sunulmuştur.

A very Rare PAX3 Gene Variant Identified in Waardenburg Syndrome: C.232G>A(p.Val78Met)

Waardenburg Syndrome (WS); it was first defined by PJ Waardenburg. This disease is caused by the physical absence of melanocytes in the stria vascularis of the skin, hair, eyes or cochlea. It is characterized by the association of pigmentation abnormalities including poliosis (white forelock on the hair), hypopigmented macules, bright blue eyes or heterochromic iris and sensorineural hearing loss. Six gene mutations are blamed in this syndrome. These; PAX3 (Paired box 3 transcription factor) gene, MITF (Microphthalmia-associated transcription factor) gene, EDN3 (Endothelin 3) gene, EDNRB (Endothelin receptor type B) gene, SOX10 (Sry bOX10 transcription factor) gene and SNAI2 (Snail homolog 2) are genes. It’s a very rare disease, its prevalence is 1/42000. It is seen equally in men and women. In this article, a 2-month-old rare case diagnosed with Waardenburg Syndrome by detecting c.232G> A (p.Val78Met) pathogenic variant in exon 2 of the PAX3 gene is presented.

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