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Updated Kidney Panels

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As a leading provider of genetic testing for inherited kidney disorders, we are pleased to announce updates to three Polycystic Kidney Disease testing panels, Hereditary Cystic Kidney Diseases, Nephrotic Syndrome (NS)/Focal Segmental Glomerulosclerosis (FSGS) panel,  and our Congenital Abnormalities of the Kidney and Urinary Tract (CAKUT) panel. The updates involve adding new genes and copy number variant (CNV) detection via sequencing to increase clinical sensitivity.

Early diagnosis of kidney disease is important for establishing optimal maintenance and treatment plans. This is why, at PreventionGenetics, we’re constantly striving to provide the best genetic tests.  

About Polycystic Kidney Disease

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is the most common inherited kidney disorder with a prevalence of 1 in 400 to 1,000 people worldwide. Finding the genetic cause of the condition is challenging due to the complexity of the main gene involved in the condition, PKD1, which is responsible for 85% of cases of ADPKD.  

The PKD1 gene is difficult to sequence because of its size (46 exons), high G-C rich content and, most importantly, exons 1-33 have six pseudogenes (PKD1P1–P6) that are located nearby. These pseudogenes share nearly 98% sequence similarity to exons 1-33 of PKD1. 

Although capture-based Next-Generation Sequencing (NGS) has become the primary platform for molecular diagnosis, NGS has limits in sequencing paralogous genes like PKD1 (Mandelker et al. 2016. PubMed ID: 27228465). To sequence exons 1-33 of the PKD1 gene correctly, other complementary methodologies, such as, multiple long-range polymerase chain reaction (PCR) amplifications need to be used for the molecular diagnosis of ADPKD patients in both clinical and research settings (Rossetti et al. 2012. PubMed ID: 22383692; Tan et al. 2014. PubMed ID: 24374109). 

Polycystic Kidney Disease Testing at PreventionGenetics

At PreventionGenetics, we adapted this strategy with careful assay design and an extensive testing of positive controls. To ensure the highest quality results for patients, we perform Sanger and NGS simultaneously for PKD1. The availability of Sanger sequencing permits efficient targeted testing of causative variants in relatives of the proband. 

To supplement CNV detection via sequencing, we also offer MLPA for the PKD1 gene. Our Autosomal Dominant and Recessive Polycystic Kidney Disease panel provides 100% coverage of all coding exons of the genes listed, plus ~10 bases of flanking noncoding DNA. 

Our Polycystic Kidney Disease test menu includes:

 About Congenital Abnormalities of the Kidney and Urinary Tract

Congenital anomalies of kidney and urinary tract (CAKUT) encompass a wide spectrum of structural malformations of the kidney and/or urinary tract due to defects during embryonic kidney development, accounting for 40-50% of children with chronic kidney disease worldwide (Sanna-Cherchi et al. 2018. PubMed ID: 29293093; Vivante et al. 2014. PubMed ID: 24398540; Nicolaou et al. 2015. PubMed ID: 26281895). The most common malformation is ureteropelvic junction obstruction (~20%). Other common clinical features within the CAKUT spectrum include renal agenesis, renal hypodysplasia, multicystic dysplastic kidney, hydronephrosis, megaureter, ureter duplex, vesicoureteral reflux (VUR), and posterior urethral valves. Age of onset of CAKUT varies from in utero to adulthood.

Congenital Abnormalities of the Kidney and Urinary Tract Testing at PreventionGenetics

For this test, sequencing of 49 genes is performed using an exome-based approach. CNVs are also detected using NGS data. All reported pathogenic, likely pathogenic, and variants of uncertain significance of interest are confirmed by Sanger sequencing. All CNVs are confirmed using another technology such as aCGH, MLPA, or PCR before they are reported. Since this test is performed using exome capture probes, a reflex to any of our exome based tests is available (PGxome, PGxome Custom Panels). For additional information and limitations, please see our full test description.

Our panel:

Nephrotic Syndrome/Focal Segmental Glomerulosclerosis

PreventionGenetics has also released an updated Nephrotic Syndrome (NS)/Focal Segmental Glomerulosclerosis (FSGS) Panel.  This updated panel includes the addition of eight new genes, MAGI1, SGPL1, OSGEP, TP53RK, TPRKB, LAGE3, KAT2B, and LAMA5, and CNV detection. 

Kidney-Related Disorders Tests at PreventionGenetics

PreventionGenetics also offers panels for many other kidney related disorders, including:

 

To review our full Nephrology test menu, click here.

Don’t see what you need?

If you are interested in a panel that is not currently offered our menu, build a custom panel on our whole-exome sequencing platform using our Custom Panel Tool.

Read more about the quality and distinguishing features at PreventionGenetics. 

Put us to the Test! 

 

Citations

Mandelker et al. 2016. Genetics in Medicine.  PubMed ID: 27228465

Nicolaou et al. 2015. Nature Reviews. Nephrology. 11, pages 720–731. PubMed ID: 26281895

Rossetti et al. 2012. Journal of the American Society of Nephrology.  23: 915-933.  PubMed ID: 22383692

Sanna-Cherchi et al. 2018. The Journal of Clinical Investigation. 128(1):4–15. PubMed ID: 29293093

Tan et al. 2014. The Journal of Molecular Diagnostics.  16(2): 216-228. PubMed ID: 24374109

Vivante et al. 2014. 29(4): 695-704. PubMed ID: 24398540