Scientific background:

Summary: Mutations of the nephrocystin 3 gene cause autosomal recessive adolescent Nephronophthisis or Renal-hepatic-pancreatic dysplasia (RHPD).

Pathology: Gene mutations cause alteration of tubular basement membrane, degeneration and dilatation of tubules, which finally leads to generalized tubulo-interstitial sclerosis. Cysts predominantly appear at the cortico-medullary junction.

Methodology:

	clinical test	Method		Genomic sequencing of the entire coding region
		Turn-around time		30 working days
		Effort		medium
		Specimen		DNA
		Quality assessment		Internal quality control only
	All known and new missense, nonsense and splice mutations can be detected.
	clinical test	Method		Carrier testing
		Turn-around time		5 working days
		Effort		little
		Specimen		DNA
		Quality assessment		Internal quality control only
	The test is only specific about the mutation already known in this kindred.
	research test	Method		Gene dosage measurements
		Turn-around time		30 working days
		Effort		30 working days
		Specimen		DNA
		Quality assessment		Internal quality control only
	Of the gene rearrangements, this method is useful to detect large deletions or duplications.

Literature: 

Olbrich H et al. (2003) Mutations in a novel gene, NPHP3, cause adolescent nephronophthisis, tapeto-retinal degeneration and hepatic fibrosis.
Omran H et al. (2000) Identification of a new gene locus for adolescent nephronophthisis, on chromosome 3q22 in a large Venezuelan pedigree.
Omran H et al. (2002) Identification of a gene locus for Senior-Løken syndrome in the region of the nephronophthisis type 3 gene.
Komatsuda A et al. (2006) Analysis of the NPHP genes in two Japanese patients with suspected sporadic juvenile or adolescent nephronophthisis.