Ağır Biyotinidaz Eksikliği Olgusunda Yeni Çift Homozigot BTD Gen Mutasyonu

Abstract

Biyotinidaz eksikliği, nadir görülen otozomal çekinik olarak kalıtılan bir hastalıktır. Erken yenidoğan döneminde tedavi edilmezse ciddi nörolojik kusurlara, metabolik bozukluklara, komaya ve ölüme neden olabilir. Yenidoğanlarda biyotinidaz eksikliği taraması ve biyotin takviyesi ile erken tedavi, semptomların çoğunun ortaya çıkması engellenebilir. Biyotinidaz enzimi, BTD geni tarafından kodlanır. BTD geninde 165'ten fazla mutasyon tanımlanmıştır. Bu olgu bildiriminde Ulusal Yenidoğan Tarama programında tespit edilen, BTD geninde homozigot çift mutasyon saptanan nadir bir tablo sunulmuş olup yeni bir allelik varyant ve genotip bildirilmiştir. Özellikle akraba evliliklerinin sık rastlanıldığı toplumlarda; yaygın görülen mutasyonlar haricinde farklı genetik tabloların da görülebileceği akılda tutulmalıdır.

Keywords

• Doğumsal metabolik hastalıklar
• biyotinidaz eksikliği
• yenidoğan taraması

A Novel Double Homozygous BTD Gene Mutation in A Case of Profound Biotinidase Deficiency

Abstract

Biotinidase deficiency is a rare autosomal recessive inherited metabolic disorder. If not treated in the early neonatal period, it can cause serious neurological defects, metabolic abnormalities, coma and death. Screening for biotinidase deficiency in newborns and early treatment with free biotin supplementation can prevent all symptoms from occurring. The biotinidase enzyme is encoded by the BTD gene. More than 165 mutations have been identified in the BTD gene. In this case report; a rare case with homozygous double mutation in the BTD gene is presented; and a new allelic variant and genotype is defined. Especially in societies where consanguineous marriages are common; it should be kept in mind that apart from common mutations, different genetic variants may also be seen.

Keywords

• Inborn errors of metabolism
• biotinidase deficiency
• newborn screening

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