Renal Tubulopathies and related disorders
Gene: SLC26A1
ClinGen Tubulopathy GCEP meeting 07/07/22 - gene disease association disputed, with the following factors cited:
- Associated phenotypes in the literature not consistent (nephrolithiasis not always reported, once reported in conjunction with nephrotic syndrome and in another instance with proximal Faconi renotubular syndrome - with each of these phenotypes involving different parts of the renal tubule/glomeruli)
- x1 convincing mouse model, but functional studies in humans not convincing
- Published variants prevalent in population database including instance of reported compound het variants being prevalent as compound het in gnomAD (identified through reviewing variant co-occurence) - c.554C>T (p.Thr185Met) and c.1073C>T (p.Ser358Leu)Created: 7 Jul 2022, 1:29 a.m. | Last Modified: 7 Jul 2022, 1:29 a.m.
Panel Version: 0.67
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Conflicting evidence for gene-disease association:
PMID: 30383413 - Whittamore et al 2019 - were unable to reproduce the hyperoxaluria, hyperoxalemia, and urolithiasis of the original SAT-1-KO mouse model.
PMID: 27125215 - Wu et al 2016 - report that Human SLC26A1-mediated anion exchange differs from that of its rodent orthologs. Also using Xenopus oocytes they find that the C41W, A56T (also reported by Gee et al) variants found in a Mexican child with recessive proximal tubular Fanconi Syndrome and the Q566R and M132T variants from Dawson et al 2013 did not alter the functional properties tested of SLC26A1 and so the proposal that these are pathogenic variants for Renal Fanconi Syndrome disease or nephrolithiasis is NOT supported.
PMID: 27210743 - Gee et al 2016 - report 2 unrelated individuals. Case 1 - individual of Macedonian descent (A3054-21) who is from non-consanguineous parents and clinically presented with acute renal failure due to bilateral obstructive calculi, nephrocalcinosis, and bilateral ureteropelvic junction obstruction. Two compound heterozygous missense mutations (c.554C>T, p.Thr185Met and c.1073C>T, p.Ser358Leu) in SLC26A1 are reported. They have minor allele freq below 0.0006 in dbSNP. Case 2 - European-American boy (B641-12) who had nephrolithiasis and was born to consanguineous parents. A homozygous missense mutation (c.166G>A, p.Ala56Thr) in SLC26A1 was found. Its minor allele frequency is 0.0002 in dbSNP.
PMID: 24250268 - Dawson et al 2013 - screened the SLC26A1 gene in a cohort of 13 individuals with recurrent calcium oxalate urolithiasis. Found one individual was heterozygous R372H; 4 individuals were heterozygous Q556R; one patient was homozygous Q556R; and one patient with severe nephrocalcinosis (requiring nephrectomy) was homozygous Q556R and heterozygous M132T. The Q556R variant is found at a high allele frequency (0.3484 in NCBI).
PMID: 20160351 - Dawson et al 2010 - Sat1-/- mice (SLC26A1) exhibited hyperoxaluria with hyperoxalemia, nephrocalcinosis, and calcium oxalate stones in their renal tubules and bladder.
Summary:
Although there are 3+ cases (2 biallelic in Gee et al, 3 monalleleic and 2 biallelic in Dawson et al 2013), plus a mouse model (Dawson et all 2010), the high minor allele frequency of the Q556R variant and the lack of altered function in protein with the A56T and M132T variants (Wu et al), and the lack of reproducibility of the mouse model phenotype cast doubt on the causative role of these variants.Created: 9 Sep 2021, 6:30 a.m. | Last Modified: 9 Sep 2021, 6:45 a.m.
Panel Version: 0.54
Mode of inheritance
BOTH monoallelic and biallelic, autosomal or pseudoautosomal
Phenotypes
Nephrolithiasis, calcium oxalate, MIM#167030
Publications
gene: SLC26A1 was added gene: SLC26A1 was added to Renal Tubulopathies and related disorders. Sources: KidGen_MetabolicRenal v38.1.0,Expert Review Red Mode of inheritance for gene: SLC26A1 was set to BOTH monoallelic and biallelic, autosomal or pseudoautosomal Publications for gene: SLC26A1 were set to 27125215; 20160351; 30383413; 27210743 Phenotypes for gene: SLC26A1 were set to Nephrolithiasis, calcium oxalate, MIM#167030