2,8-Dihydroxyadenine Urolithiasis Type IA

Test Overview:

Adenine phosphoribosyltransferase (APRT) is an enzyme involved in the purine salvage pathway, where it catalyzes the conversion of adenine and 5-phosphoribosyl-1-pyrophosphate to adenosine monophosphate [1]. In the absence of APRT, xanthine dehydrogenase (XDH) converts adenine into 2,8-dihydroxyadenine (2,8-DHA), a compound that is highly insoluble in urine. Acute kidney injury may occur from urinary tract obstruction by calculi, and chronic kidney disease is a common sequela caused by crystalline nephropathy. The age of onset varies, with many affected individuals remaining asymptomatic until adulthood.


Urinary system / Urologic - Associated with the kidneys, bladder, ureters and urethra


Adenine phosphoribosyltransferase (APRT) on chromosome 5

Variant Detected:

Base Substitution c.260G>A p.Arg87Gln


Low-Moderate. This disease can cause some discomfort and/or dysfunction in the affected animal. It does not generally affect life expectancy.

Mode of Inheritance:

Autosomal Recessive

Research Citation(s):

Furrow et al. Mol Genet Metab, An APRT mutation is strongly associated with and likely causative for 2,8-dihydroxyadenine urolithiasis in dogs. (2014) 111;3, 399–403

Associated Breed(s):

Mixed Breed, Native American Indian Dog,