A new point mutation in a hypoxanthine phosphoribosyltransferase-deficient patient.
A 12-year-old boy was referred because of abdominal pain, gross hematuria, and passage of stones. Further evaluation showed growth delay, low average range of intellectual functioning, and a speech articulation disorder. No signs of self-mutilation or self-injurious behavior were present. He had hyperuricemia, hyperuricosuria, uric acid crystalluria, uric acid calculi, macrocytosis, megaloblastic bone marrow changes, and mild anemia. Hypoxanthine phosphoribosyltransferase (HPRT) enzyme activity was reduced to approximately 26% of normal. Polymerase chain reaction-single strand conformational polymorphism analysis of the HPRT gene in DNA isolated from the patient's blood lymphocytes revealed a single nucleotide substitution at codon 200 in exon 8. The base change was a guanine to cytosine transversion, resulting in the conservative amino acid substitution of threonine in place of arginine. To our knowledge, this mutation has not previously been reported.
Hidalgo-Laos
R I
RI
Department of Pediatrics, University of Florida College of Medicine, Gainesville 32610-0296, USA.
Kedar
A
A
Williams
C A
CA
Neiberger
R E
RE
D002648:Child; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000172:deficiency* / Q000235:genetics*; D007669:Kidney Calculi / Q000235:genetics / Q000652:urine; D007926:Lesch-Nyhan Syndrome / Q000235:genetics* / Q000652:urine; D008297:Male; D017354:Point Mutation / Q000235:genetics* / Q000502:physiology*; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D017422:Sequence Analysis, DNA; D014545:Urinary Calculi / Q000628:therapy
D007041:Hypoxanthine Phosphoribosyltransferase