ARPKD Known PKHD1 Variant Prenatal Testing (PT2)
Information for Ordering
Acceptable Specimen Types• Please provide fresh blood sample (3-6 ml, EDTA) for maternal cell contamination studies with (or in advance) of submitted specimen. A delay in receipt may delay turnaround time
• Direct CVS (minimum 10 mg pure villi)
• Direct amniotic fluid (min. 10 ml fluid)
• 2 T25 flasks of cultured CVS (>70% confluent)
• 2 T25 flasks of cultured amniocytes (>70% confluent)
*Please Note: cultured cells are required for any multiexonic deletion/duplication targeted analysis
6 working days
$1,000 (USD – institutional/self-pay)
CPT: 81265 and 81403 (x2)
Z code: ZB67M
Candidates for Testing
ARPKD testing services are offered to established patients and families with previously identified PKHD1 pathogenic variants who want to prepare for prenatal/pre-implantation diagnosis and for predictive testing for individuals at risk of inheriting an already known variant.
Please find specimen requirement specifications above.
All submitted specimens must be sent at room temperature. DO NOT ship on ice.
Specimens must be packaged to prevent breakage and absorbent material must be included in the package to absorb liquids in the event that breakage occurs. Also, the package must be shipped in double watertight containers (e.g. a specimen pouch + the shipping company’s diagnostic envelope).
To request a sample collection kit, please click here or email medgenomics@uabmc.edu to complete the specimen request form.
Please contact the MGL (via email at medgenomics@uabmc.edu, or via phone at 205-934-5562) prior to sample shipment and provide us with the date of shipment and tracking number of the package so that we can better ensure receipt of the samples.
About
Disorder BackgroundAutosomal Recessive Polycystic Kidney Disease (ARPKD) is characterized by enlarged cystic kidneys and hepatic fibrosis. The diagnosis is often made pre- or neonatally, but some patients are still diagnosed later in life. The severity varies widely, with a high mortality rate in the first months of life. ARPKD is one of the more common hereditary childhood nephropathies with an estimated incidence of 1:20,000-1:40,000. The carrier frequency in the general population is estimated to be 1 in 70 to 1 in 100. Variants in PKHD1 are scattered throughout the gene. Most families carry their own “private” variants. For more information on the condition please refer to the review on the GeneTests website and Online Mendelian Inheritance in Man.
The gene for ARPKD, PKHD1 (Polycystic Kidney and Hepatic Disease 1), resides on chromosome 6p21-p12, spans 470 kb of genomic DNA and is the only gene known to be associated with the wide clinical spectrum of autosomal recessive polycystic kidney disease. 86 exons have been identified and multiple alternative transcripts are known. Over 300 variants have been reported. Missense, nonsense, frameshift, splicing and multi-exon deletions can occur and the variants are located throughout the length of the gene, with no major variant hotspots known, as shown in the PKHD1 variant database.
We offer targeted detection of a previously characterized pathogenic variant within the family. DNA is extracted directly and the target region is amplified and directly sequenced. To offer this testing service, the proband’s variant must be identified by our laboratory before testing relatives.
REFERENCES available here.
Other related test options:
- ARPKD Known PKHD1 Mutation Linkage Analysis for Informativity (PKDL) & Prenatal Linkage (PKDPL)
- ARPKD Known Mutation Testing (KT2)
For more information, test requisition forms, or sample collection and mailing kits, please call: 205-934-5562.