In contrast, some hair roots from carriers of HPRT deficiency contained two zones of activity with the same relative proportion of APRT and HPRT as hair roots of normal homozygotes, while others contained decreased amounts of HPRT activity.
The classical Lesch-Nyhan syndrome has the deficiency of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) activity as the result of mutation in the structural gene for the enzyme located on the X chromosome and is believed to be of X-linked recessive or sex-linked mode of inheritance.
The absence of activity of the enzyme hypoxanthine-guanine phosphoribosyltransferase (EC 2.4.2.8) is known to be the cause of the Lesch-Nyhan syndrome.
We have investigated the molecular basis of hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency in a patient who presented with the Lesch-Nyhan syndrome.
The mutation in HPRTFlint disrupts a strongly conserved region among PRTases from Escherichia coli, rodents and man, suggesting an important role for this region for the normal function of HPRT.
The mutation in HPRTFlint disrupts a strongly conserved region among PRTases from Escherichia coli, rodents and man, suggesting an important role for this region for the normal function of HPRT.
Sequencing analysis of the amplified DNA from three different patients with HPRT deficiency implied three unique molecular abnormalities: 1) one single-base substitution at codon 54 (from ATG to CTG) resulting in the replacement of methionine with leucine in an LN patient, 2) two single-base substitutions at codon 179 (from GTT to GGT) and at codon 180 (from GGA to AGA) resulting in the replacement of valine with glycine and glycine with arginine in a gouty patient, and 3) 51 nucleotide deletion between nucleotides 747 and 797 resulting in the formation of shorter sized HPRT mRNA and putative two amino-acid deleted HPRT protein in another gouty patient.
Erythrocyte assays for hypoxanthine guanine phosphoribosyltransferase (HGPRT) activity performed on two male half-siblings with hyperuricemia, produced results consistent with classic Lesch-Nyhan syndrome.
Complete deficiency of the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT) results in a devastating neurological disease, the Lesch-Nyhan syndrome.
Previous characterization of a mutant form of HPRT, HPRTYale, from a subject with the Lesch-Nyhan syndrome revealed normal mRNA and protein concentrations, no residual catalytic activity, and cathodal migration upon PAGE.
Previous characterization of a mutant form of HPRT, HPRTYale, from a subject with the Lesch-Nyhan syndrome revealed normal mRNA and protein concentrations, no residual catalytic activity, and cathodal migration upon PAGE.