rs768245266

Positions:

• chr7-107683351-T-TG

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000441.2(SLC26A4):​c.916dupG​(p.Val306fs) variant causes a frameshift, splice region change. The variant allele was found at a frequency of 0.00000124 in 1,613,480 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SLC26A4 NM_000441.2 frameshift, splice_region
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 6.05

Genes affected

SLC26A4 (HGNC:8818): (solute carrier family 26 member 4) Mutations in this gene are associated with Pendred syndrome, the most common form of syndromic deafness, an autosomal-recessive disease. It is highly homologous to the SLC26A3 gene; they have similar genomic structures and this gene is located 3' of the SLC26A3 gene. The encoded protein has homology to sulfate transporters. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-107683351-T-TG is Pathogenic according to our data. Variant chr7-107683351-T-TG is described in ClinVar as [Likely_pathogenic]. Clinvar id is 370192.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SLC26A4	NM_000441.2	c.916dupG	p.Val306fs	frameshift_variant, splice_region_variant	7/21	ENST00000644269.2	NP_000432.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SLC26A4	ENST00000644269.2	c.916dupG	p.Val306fs	frameshift_variant, splice_region_variant	7/21		NM_000441.2	ENSP00000494017.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152148 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000192

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251278 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135804

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000163

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461332 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727020

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152148 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74318

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000192

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Pendred syndrome Pathogenic:4

Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Dec 11, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Apr 01, 2024	Variant summary: SLC26A4 c.916dupG (p.Val306GlyfsX24) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 1.2e-05 in 251278 control chromosomes (gnomAD). c.916dupG has been reported in the literature in multiple individuals affected with non syndromic enlarged vestibular aqueduct (example: Chai_2013). These data indicate that the variant is very likely to be associated with disease. The following publication has been ascertained in the context of this evaluation (PMID: 23918157). ClinVar contains an entry for this variant (Variation ID: 370192). Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Sep 05, 2021	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Dec 02, 2020	- -

Autosomal recessive nonsyndromic hearing loss 4 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 16, 2024	- -
Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	Oct 27, 2017	A heterozygous duplication variant, NM_000441.1(SLC26A4):c.916dupG, has been identified in exon 7 of 21 of the SLC26A4 gene. This variant is predicted to cause a frameshift from amino acid position 306 and introduce a stop codon 24 residues downstream, NP_000432.1(SLC26A4):p.(Val306Glyfs*24), resulting in loss of protein function either through truncation (involving half of the protein including functional domains) or nonsense-mediated decay.This variant is present in the gnomAD database with a global frequency of 0.0014% (2 in 277028, 0 homozygotes) and in East Asian populations at a frequency of 0.02% (4 in 18862, 0 homozygotes). The variant has been previously described as pathogenic in multiple families withsevere to profoundhearing loss(ClinVar, Li, Q. et al. (2012), Lee, HJ. et al. (2014),Mori, K.et al. (2016), Wang, Q-J. et al. (2007),Jung, J. et al. (2017)). Based on current informationthis variant has been classified as PATHOGENIC. -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 25, 2024	This sequence change creates a premature translational stop signal (p.Val306Glyfs*24) in the SLC26A4 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SLC26A4 are known to be pathogenic (PMID: 16283880, 25394566, 26252218, 26445815). This variant is present in population databases (rs768245266, gnomAD 0.02%). This premature translational stop signal has been observed in individuals with non-syndromic hearing loss and Pendred syndrome (PMID: 14715652, 17718863, 21366435, 26252218). This variant is also known as 916_917insG and 916insG. ClinVar contains an entry for this variant (Variation ID: 370192). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jun 22, 2020	Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Published functional studies demonstrate a damaging effect on iodide transport (Gillam et al., 2004); This variant is associated with the following publications: (PMID: 30275481, 30896630, 31827275, 31581539, 30842343, 26252218, 14715652, 27240500, 20483489, 23302201, 17718863) -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs768245266; hg19: chr7-107323796;