Laboratory for Molecular Diagnostics
Center for Nephrology and Metabolic Disorders

FXYD domain-containing ion transport regulator 2

The gene encodes an ion transporter regulator, whose mutations cause hypomagnesaemia with hypocalciuria.

Epidemiology

Epidemiological data concerning this disease are very restricted.

Gene Structure

The gene is about 9,2 kb in size. Alternatively the gene is named sodium-potassium ATPase gamma-1 polypeptide (ATP1G1). It is located on chromosome 11 at position 11q23. It consists 7 exons. Two different isotypes using different promotors are described.

Phenotype

Only one loss-of-function mutation is known so far. In this family also a hypocalciuria occurred. The mode of inheritance was autosomal dominant.

Pathology

The gene is transcribed in pancreas in kidney. In the latter, it is found in the distal convolution. The different isotypes of the protein contain 58 or 66 amino acids. The gene forms a transmembraneous domain and functions as a regulating component of the sodium-potassium ATPase.

Interpretation

Family counseling is the only therapeutical consequence at the moment.

Genetests:

Clinic Method Carrier testing
Turnaround 5 days
Specimen type genomic DNA
Clinic Method Genomic sequencing of the entire coding region
Turnaround 10 days
Specimen type genomic DNA
Clinic Method Massive parallel sequencing
Turnaround 25 days
Specimen type genomic DNA

Related Diseases:

Isolated dominant hypomagnesemia
FXYD2

References:

1.

Meij IC et al. (2000) Dominant isolated renal magnesium loss is caused by misrouting of the Na(+),K(+)-ATPase gamma-subunit.

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2.

Kantorovich V et al. (2002) Genetic heterogeneity in familial renal magnesium wasting.

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Update: Sept. 26, 2018