rs121908365
Variant summary
Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong
The NM_000441.2(SLC26A4):c.397T>A(p.Ser133Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000279 in 1,435,244 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S133P) has been classified as Likely pathogenic.
Frequency
Consequence
NM_000441.2 missense
Scores
Clinical Significance
Conservation
Publications
- autosomal recessive nonsyndromic hearing loss 4Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, PanelApp Australia, Labcorp Genetics (formerly Invitae)
- Pendred syndromeInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae), ClinGen
- athyreosisInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- thyroid hypoplasiaInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- hearing loss, autosomal recessiveInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
Genome browser will be placed here
ACMG classification
Our verdict: Pathogenic. The variant received 19 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes Cov.: 31
GnomAD4 exome AF: 0.00000279 AC: 4AN: 1435244Hom.: 0 Cov.: 26 AF XY: 0.00000279 AC XY: 2AN XY: 715846 show subpopulations
Age Distribution
GnomAD4 genome Cov.: 31
ClinVar
Submissions by phenotype
Pendred syndrome Pathogenic:3
Variant summary: SLC26A4 c.397T>A (p.Ser133Thr) results in a conservative amino acid change in the encoded protein sequence. Three of four in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251354 control chromosomes (gnomAD). c.397T>A has been reported in the literature in individuals affected with Pendred Syndrome (Fugazzola_2002, Borck_2003). These data indicate that the variant is likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function and this variant affected the SLC26A4 protein function (Wasano_2020). ClinVar contains an entry for this variant (Variation ID: 4834). Based on the evidence outlined above, the variant was classified as pathogenic. -
- -
This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -
Autosomal recessive nonsyndromic hearing loss 4 Pathogenic:1Other:1
in vitro experiment -
Analysis of patient-derived RNA indicates that SLC26A4 c.397T>A leads to skipping of exon 4 (111bp) in message, with loss of aa 102-138 of TM1 and TM2 (Abu Rayyan 2020). The variant is homozygous in a Palestinian child with severe to profound pre-lingual hearing loss (Abu Rayyan 2020). It is absent from 1300 Palestinian controls and from gnomAD v2.1.1. -
not provided Pathogenic:1
This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with Pendred syndrome (PMID: 11919333, 12788906). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 4834). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt SLC26A4 protein function. Studies have shown that this missense change results in skipping of exon 4, but is expected to preserve the integrity of the reading-frame (PMID: 32747562). For these reasons, this variant has been classified as Pathogenic. This sequence change replaces serine, which is neutral and polar, with threonine, which is neutral and polar, at codon 133 of the SLC26A4 protein (p.Ser133Thr). RNA analysis indicates that this missense change induces altered splicing and likely results in a shortened protein product. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at