Detection of biotinidase gene mutations in Turkish patients ascertained by newborn and family screening


KARACA M., ÖZGÜL R. K. , ÜNAL O., Yucel-Yilmaz D. , KILIÇ M., Hismi B., ...More

EUROPEAN JOURNAL OF PEDIATRICS, vol.174, no.8, pp.1077-1084, 2015 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 174 Issue: 8
  • Publication Date: 2015
  • Doi Number: 10.1007/s00431-015-2509-5
  • Title of Journal : EUROPEAN JOURNAL OF PEDIATRICS
  • Page Numbers: pp.1077-1084
  • Keywords: BD, Biotinidase deficiency, BTD, Gene coding for BTD, Newborn screening, Turkish population, SYMPTOMATIC CHILDREN, UNITED-STATES, COMMON-CAUSE, DEFICIENCY, IDENTIFICATION, LOCALIZATION, CONSERVATION, EXPRESSION, DIAGNOSIS, DISEASE

Abstract

The incidence of biotinidase deficiency in Turkey is currently one of the highest in the world. To expand upon the information about the biotinidase gene (BTD) variations in Turkish patients, we conducted a mutation screening in a large series (n = 210) of probands with biotinidase deficiency, using denaturing high-performance liquid chromatography and direct DNA sequencing. The putative effects of novel mutations were predicted by computational program. Twenty-six mutations, including six novels (p.C143F, p.T244I, c.1212-1222del11, c.1320delG, p.V457L, p.G480R) were identified. Nine of the patients were symptomatic at the initial clinical assessment with presentations of seizures, encephalopathy, and lactic acidemia. The most common mutation in this group of symptomatic patients was c.98-104 del7ins3. Among the screened patients, 72 have partial and 134 have profound biotinidase deficiency (BD) of which 106 are homozygous for BTD mutations. The common mutations (p.R157H, p.D444H, c.98-104del7ins3, p.T532M) cumulatively accounted for 72.3 % of all the mutant alleles in the Turkish population.