A novel L218p mutation in nadh-cytochrome b5 reductase associated with type i recessive congenital methemoglobinemia

Arkoglu T., Yarali N. , Kara A., Bay A., Bozkaya I. O. , Tunc B., ...More

Pediatric Hematology and Oncology, vol.26, no.5, pp.381-385, 2009 (Journal Indexed in SCI Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 26 Issue: 5
  • Publication Date: 2009
  • Doi Number: 10.1080/08880010902979233
  • Title of Journal : Pediatric Hematology and Oncology
  • Page Numbers: pp.381-385
  • Keywords: Congenital methemoglobinemia, Cyanosis, Cytochrome b5 reductase deficiency


The presence of central cyanosis that is unrelated to cardiopulmonary causes alerts clinicians to a possible diagnosis of methemoglobinemia. Congenital methemoglobinemia due to deficiency of nicotinamide-adenine dinucleotide (NADH)-cytochrome b5 reductase (cb5r) is an autosomal recessive disorder characterized by life long cyanosis. Here we report a six-year old boy who presented with central cyanosis and upon examination revealed a methemoglobin level of 19.0%. Sequencing the CYB5R3 gene identified a homozygous TC transition at base c.653, which changed codon 218 from leucine to proline (L218P) in cb5r protein. Treatment with ascorbic acid relieved the cyanosis and returned methemoglobin levels to normal. © Informa Healthcare USA, Inc.