Human hypoxanthine-guanine HGPRT

HUMAN HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE (HGPRT) PURIFICATION AND PROPERTIES... 

HG-OES hydride generation optical emission spectrometry (see HG-AES) HGPRT-test hypoxanthine-guanine-phos-pho-ribosyl-transferase test, a mutagenicity test with mammalian cells HHPN hydraulic high pressure nebulizer HIV human immunodeficiency virus HMDE hanging mercury drop electrode... 

Cultured human skin fibroblasts are commonly utilized in the detection of hemizygosity and heterozygosity for hypoxanthine-guanine phosphoribosyltrans-ferase (HGPRT) deficiency. Two obstacles are encountered in the determination of HGPRT and adenine phosphoribosyl-transferase (APRT) in extracts of cultured skin fibroblasts the sensitivity of these enzymes in dilute cell suspension to freezing and thawing (l), and the presence of nucleotidase activity (2). 

A. A. van Zeeland, Y. C. E. M. de Ruijfer, and J. W. I. M. Simons, The role of 8-azagua-nine in the selection from human diploid cells of mutants deficient in hypoxanthine-guanine-phosphoribosyl-transferase (HGPRT), Mutat. Res. 23, 55 (1974). 

Several mammalian cell systems have been developed in order to determine the potential of food additives and other environmental chemicals to cause gene locus mutations. Some employ rodent cells, as described by Clive and Spector , whereas others use diploid human lymphoblasts as indicator organisms The human lymphoblast system measures the response of hypoxanthine guanine phosphoribosyl transferase (hgprt). Considerable care must be used with these systems for example, the importance of phenotypic lag has been clearly demonstrated by Penman and Thilly. ... 

Human platelets do not synthesize nucleotides de novo (l) but have been demonstrated to possess salvage pathways utilizing adenine and adenosine (2,3). On the other hand, no evidence has been reported as yet for the presence of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) in human platelets. 

Recent advances in the understanding of human purine metabolism have been stimulated by the discovery of specific inborn errors of this pathway in man. In particular, the demonstration of the deficiency of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) in the Lesch-Nyhan syndrome and in some patients with gout has contributed essential information on the regulation of purine biosynthesis novo and on the critical role of this reutilization pathway in central nervous system function in man. The search for other disorders led to the description of a partial deficiency of adenine phosphoribosyltransferase (APRT) in four members in three generations of one family. Each of the subjects partially deficient in APRT exhibited a normal serum urate concentration and the propositus had a normal excretion of uric acid (Kelley, et al., 1968). We have investigated a second family partially deficient in APRT (Fox and Kelley, in press). 

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