Xanthurenic aciduria due to a mutation in KYNU encoding kynureninase.

Abstract

Massive urinary excretion of xanthurenic acid, 3-hydroxykynurenine and kynurenine, known as xanthurenic aciduria or hydroxykynureninuria, in a young Somali boy suggested kynureninase deficiency. Mutation analysis of KYNU encoding kynureninase of the index case revealed homozygosity for a c.593 A > G substitution leading to a threonine-to-alanine (T198A) shift. A younger brother was found to have a similar excretion pattern and the same genotype. At present, neither of the two boys has symptoms of niacin deficiency. This is the first report linking xanthurenic aciduria to a mutation in the gene encoding kynureninase.

• Authors: M Christensen, M Duno, A M Lund, F Skovby, E Christensen
• Journal: Journal of inherited metabolic disease (J Inherit Metab Dis) Vol. 30 Issue 2 Pg. 248-55 (Apr 2007) ISSN: 1573-2665 [Electronic] United States
• PMID: 17334708 (Publication Type: Case Reports, Journal Article)

Chemical References

• Xanthurenates
• Threonine
• xanthurenic acid
• Guanine
• Hydrolases
• kynureninase
• Adenine
• Alanine

Topics

• Adenine
• Alanine
• Amino Acid Metabolism, Inborn Errors (genetics)
• Amino Acid Substitution
• Child
• DNA Mutational Analysis
• Genotype
• Guanine
• Homozygote
• Humans
• Hydrolases (deficiency, genetics)
• Male
• Mutation
• Pedigree
• Threonine
• Xanthurenates (urine)