The gene codes for the gamma subunit of the epithelial sodium channel, which regulates aldosteron dependend excretion of sodium in distal nephrons. Gain-of-function mutations result in Liddle syndrome whereas loss-of-function mutations lead to autosomal recessive Pseudohypoaldosternism 1.
The gene locus on chromosome 16 (16p12) is in the proximity to other components of the sodium channel. The 13 exons spread over 35kb. Only the last 12 of them become translated.
Opposite phenotypes result depending on whether a gain- or loss-of-function mutation is present.
The aldosteron-sensitive distal nephron consists of distal convoluted tubule (DCT), the connecting tubule (CNT), and the collecting duct (CD). This part of the nephron is characterized by the colocalization of the epithelial sodium channel (ENaC), the mineralocorticoid receptor, and the 11-beta hydroxysteroid dehydrogenase type 2. The gene codes for the gamma subunit of the channel. Gain-of-function mutations result in Liddle syndrome whereas loss-of-function mutations lead to Pseudohypoaldosteronism.
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 | 20 days | |
Specimen type | genomic DNA |
1. |
Swift PA et al. (2004) The epithelial sodium channel in hypertension: genetic heterogeneity and implications for treatment with amiloride. |
2. |
None (2001) Liddle syndrome: genetics and mechanisms of Na+ channel defects. |
3. |
Capasso G et al. (2005) Channels, carriers, and pumps in the pathogenesis of sodium-sensitive hypertension. |
4. |
Orphanet article Orphanet ID 118539 |
5. |
NCBI article NCBI 6340 |
6. |
OMIM.ORG article Omim 600761 |
7. |
Wikipedia article Wikipedia EN (SCNN1G) |