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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Copyright and license

How to cite

1.
Deveci K, Akar HT, Yıldız Y, Özgül RK. A Novel Double Homozygous BTD Gene Mutation in A Case of Profound Biotinidase Deficiency. Turk J Pediatr Dis [Internet]. 2023 May 29 [cited 2025 May 25];17(3):250-2. Available from: https://turkjpediatrdis.org/article/view/980