The NPHP1 gene is associated with several different conditions including Joubert syndrome, familial juvenile nephronophthisis, and Senior-Loken syndrome 1, which are all inherited in an autosomal recessive manner. Features of Joubert syndrome include distinctive cerebellar and brainstem malformations, hypotonia, developmental delay, and either episodic hyperpnea or apnea or atypical eye movements or both. Of individuals with Joubert syndrome approximately 1-2% will have a deletion of the NPHP1 gene. Nephronophthisis is characterized by anemia, polyuria, polydipsia, isothenuria, and death in uremia. Both mutations and deletions of the NPHP1 gene have been reported to cause nephronophthisis. Feature of Senior-Loken syndrome include the nephronophthisis and Leber congenital amaurosis. It is caused by a homozygous deletion of the NPHP1 gene.
This laboratory performs only Sanger sequencing of this gene.