title: A new diagnostic technique for adenylosuccinate lyase deficiency.
abstract: A convenient and simple method of diagnosing adenylosuccinate lyase (ASL) deficiency is described. This method consists of (1) isolation of SAICA riboside and S-Ado with a cation exchange resin; (2) measurement of the UV absorbance of the ammonia eluate at 270 and 250 nm; (3) calculation of the A270/A250 ratio. If the value of this ratio is less than 0.45, the patient has a normal level of ASL activity. If the value of this ratio is greater than 0.70, the patient has ASL deficiency.
mesh_terms: D000249:Adenosine Monophosphate / Q000031:analogs & derivatives / Q000652:urine; D000264:Adenylosuccinate Lyase / Q000172:deficiency*; D000620:Aminoimidazole Carboxamide / Q000031:analogs & derivatives / Q000652:urine; D002852:Chromatography, Ion Exchange; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D011686:Purine-Pyrimidine Metabolism, Inborn Errors / Q000201:enzymology*; D012263:Ribonucleosides / Q000652:urine; D013056:Spectrophotometry, Ultraviolet
chemical_list: D012263:Ribonucleosides; C043566:succinylaminoimidazole carboxamide riboside; C012168:adenylosuccinate; D000620:Aminoimidazole Carboxamide; D000249:Adenosine Monophosphate; D000264:Adenylosuccinate Lyase