Molecular detection of autosomal-dominant feline polycystic kidney disease by multiplex amplification refractory mutation system polymerase chain reaction

miR-20a is upregulated in serum from domestic feline with PKD1 mutation

Polycystic kidney disease (PKD), also known as autosomal dominant polycystic kidney disease (ADPKD) is a genetically heterogeneous condition characterized by cysts in renal parenchyma. It is the most prevalent inherited disease of domestic cats. MicroRNAs (miRNAs or ncRNA) are short, noncoding, single-stranded RNAs that may induce PKD cytogenesis by affecting numerous targets genes as well as by directly regulating PKD gene expression. We compared the relative expression profile of miR-20a, -192, -365, -15b-5p, and -16-5p from plasma and serum samples of nine domestic cats with PKD1 mutation, detected by polymerase chain reaction (PCR), and a control group (n = 10). Blood samples from cats with PKD1 mutation provide similar concentrations of microRNAs either from plasma or serum. Serum miR-20a is upregulated in PKD group with p < 0.005; Roc curve analysis showed an AUC of 90,1% with a cut-off value sensitivity of 77.8% and specificity of 100%. This data provides important information regarding renal miRNA expression in peripheral blood sampling.

Prevalence of polycystic kidney disease in Persian and Persian-related cats in western Mexico

OBJECTIVES

Autosomal dominant polycystic kidney disease (ADPKD), the most frequently diagnosed hereditary disease affecting Persian cats, is caused by a cytosine-to-adenine transversion (10063C>A) in PKD1, the gene that codes for polycystin-1. The objective of this study was to provide a preliminary estimate of the frequency of the pathogenic 10063C>A single nucleotide polymorphism (SNP) of PKD1 in Persian and Persian-related cat breeds in western Mexico.

METHODS

Blood samples were collected from 104 cats (89 Persian, seven Persian crossbreed, five Siamese and three Himalayan cats). Genotyping was performed with our proposed PCR restriction fragment length polymorphism (RFLP) assay, as well as a previously established PCR-RFLP method for validation. The genotypes of control cats were corroborated by a commercial veterinary genetics laboratory.

RESULTS

Our proposed PCR-RFLP assay and the validated PCR-RFLP methodology indicated that 24/104 (23.1%) cats in this study were heterozygous carriers of the 10063C>A SNP, including 23/89 Persian cats (25.8%) and 1/7 Persian crossbreed cats (14.3%). No Siamese or Himalayan cats were carriers. There were no discrepancies between the results obtained with our proposed assay and those obtained with the validation method or with commercial laboratory results.

CONCLUSIONS AND RELEVANCE

The carrier frequency of the PKD1 10063C>A SNP in Persian and Persian-related cat breeds in western Mexico was found to be 23.1%. ADPKD frequencies among cat populations in Mexico have not been published previously. Genotyping assays can be used to facilitate the selection of breeding stocks by local breeders and veterinarians to avoid propagation of ADPKD.

Molecular detection of polycystic kidney disease in Persian and Persian-related breeds in Iran

Objectives

This study was aimed at detecting feline autosomal dominant polycystic kidney disease in a population of Persian and Persian-related breeds by a molecular method in Iran.

Methods

Buccal swab samples were collected from 47 cats and examined with a touchdown PCR method. Additionally, partial sequencing was performed in two cats with bilateral renal cysts.

Results

Twenty-two cats (46.8%) were diagnosed as heterozygous for this mutation. Sequence analysis of two cats showed C to A point mutation in the PKD1 gene, as in previous studies.

Conclusions and relevance

Prevalence of this disease is high in Iran, highlighting the need for molecular screening tests before including cats in breeding programmes.

Feline Polycystic Kidney Disease: An Update

Polycystic kidney disease (PKD) is a disease that affects felines and other mammals, such as humans. The common name is autosomal dominant polycystic kidney disease (ADPKD) and causes a progressive development of fluid-filled cysts in the kidney and sometimes in other organs as the liver and pancreas. The formation and growth of cysts progress slowly, causing deterioration of kidney tissue and a gradual decrease in kidney function, leading to irreversible kidney failure. Feline PKD or ADPKD in humans are hereditary pathologies of autosomal dominant transmission. ADPKD is one of the genetic diseases with the highest prevalence in humans. In cats, this disease also has a high prevalence, mainly in the Persian breed, being one of the most common feline genetic diseases. Imaging tests seem to be the most reliable method for diagnosis of the disease, although more genetic tests are being developed to detect the presence of the responsible mutation. In this review, we summarize the current knowledge about feline PKD to guide future research related to an adequate diagnosis and early detection of causal mutations. It can allow the establishment of selection programs to reduce or eliminate this pathology in feline breeds.

Touchdown polymerase chain reaction detection of polycystic kidney disease and laboratory findings in different cat populations

Autosomal-dominant polycystic kidney disease (ADPKD) is the most prevalent inherited genetic disease of cats, predominantly affecting Persian and Persian-related cats. A point mutation (C→A transversion) in exon 29 of the PKD1 gene causes ADPKD, and is the specific molecular target for genetic diagnosis in cats. The current study describes a newly developed touchdown polymerase chain reaction (PCR) to detect this single point mutation, using 2 primers specific for the mutant allele, adapted from an existing multiplex amplification refractory mutation system (ARMS PCR). Furthermore, correlations between the clinical outcomes of tested animals and the results of the genetic test were investigated. A total of 334 cats were tested, 188 from the Veterinary Hospital of Small Animals at the University of Brasilia, and 146 from an anti-rabies vaccine campaign of the Federal District. A total prevalence of 9% was evident among the samples, with 33% of the Persian cats testing positive, and 7% of the Brazilian long- and shorthaired cats testing positive. Prevalence was not correlated with gender or hemogram. Positive animals exhibited hyperglobulinemia ( P = 0.02). This research demonstrated that the mutation does not only occur in Persian and Persian-related cats, and that a touchdown PCR can be used to diagnose ADPKD.