Laboratory for Molecular Diagnostics
Center for Nephrology and Metabolic Disorders

Nephrocystin 1

Homozygous or compound heterozygous mutations of NPHP1 cause nephronophthisis 1, Senior-Loken syndrome 1, or Joubert syndrome 4.

Gene Structure

The NPHP1 gene, which is located on chromosome 2 (2q13) spans about 85kb. Two spice variants exists with 20 and 4 exons. In the shorter splice variant, exon 4 is 376 bases longer.

Pathology

Nearly 80% of patients with nephronophthisis 1 show a homozygous deletion of about 290 kb. But splice and missense mutations have also been reported.[Error: Macro 'ref' doesn't exist]

Test Strategy

As in many patients a homozygous deletion of a large part of the gene is the cause of disease, in most cases the diagnosis can be proved by demonstrating amplification failure during the first step of sequencing analysis.

Genetests:

Clinic Method Carrier testing
Turnaround 5 days
Specimen type genomic DNA
Clinic Method Massive parallel sequencing
Turnaround 25 days
Specimen type genomic DNA
Clinic Method Genomic sequencing of the entire coding region
Turnaround 30 days
Specimen type genomic DNA
Clinic Method Multiplex Ligation-Dependent Probe Amplification
Turnaround 25 days
Specimen type genomic DNA

Related Diseases:

Nephronophthisis 01
NPHP1
Senior-Loken syndrome 1
NPHP1
Joubert syndrome 04
NPHP1

References:

1.

Saunier S et al. (2000) Characterization of the NPHP1 locus: mutational mechanism involved in deletions in familial juvenile nephronophthisis.

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2.

Hildebrandt F et al. (1997) A novel gene encoding an SH3 domain protein is mutated in nephronophthisis type 1.

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3.

NCBI article

NCBI 4867 [^]
4.

OMIM.ORG article

Omim 607100 [^]
5.

Orphanet article

Orphanet ID 123874 [^]
6.

Wikipedia article

Wikipedia EN (NPHP1) [^]
Update: April 29, 2019