Exome sequencing identifies compound heterozygous PKHD1 mutations as a cause of autosomal recessive polycystic kidney disease

Chin Med J (Engl). 2012 Jul;125(14):2482-6.

Abstract

Background: Autosomal recessive polycystic kidney disease (ARPKD) is a rare inherited disease, which is a disorder with multiple organ involvement, mainly the kidney and liver. It is caused by mutations in the PKHD1 gene. Here, we reported the clinical characteristics of a case with ARPKD and analyze the genetic features of this patient as well as of his father using targeted exome sequencing and Sanger sequencing.

Methods: Genomic DNA was extracted from peripheral blood leukocytes obtained from a patient with ARPKD. The mutations were identified using exome sequencing and confirmed by Sanger sequencing.

Results: The patient was diagnosed as ARPKD based on ultrasonography and abdominal computed tomography which showed polycystic changes, multiple calcinosis of both kidneys, and multiple dilated bile ducts of the liver. Compound heterozygous PKHD1 gene mutations A979G and G5935A, which lead to substitution of an asparagine for an aspartate at amino acid 327 (N327D) and a glycine for an arginine at amino acid 1979 (G1979R) respectively, were identified using targeted exome sequencing and confirmed by Sanger sequencing for the patient. In addition, the father of the patient was identified to be a carrier of heterozygous A979G mutation of this gene.

Conclusions: We identified that the compound heterozygous PKHD1 gene mutations are the molecular basis of the patient with ARPKD. Targeted exome sequencing is suitable for genetic diagnosis of single-gene inherited diseases like ARPKD in which the pathogenic gene is a large.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Exome / genetics*
  • Genetic Predisposition to Disease
  • Humans
  • Male
  • Mutation
  • Polycystic Kidney, Autosomal Recessive / genetics*
  • Receptors, Cell Surface / genetics*

Substances

  • PKHD1 protein, human
  • Receptors, Cell Surface