NM_000441.2:c.227C>G

Variant names:

• chr7-107663358-C-G
• rs1345175795
• NM_000441.2:c.227C>G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP2 PP3_Moderate PP5

The NM_000441.2(SLC26A4):​c.227C>G​(p.Pro76Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P76S) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SLC26A4 NM_000441.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 3.58
• Publications: 5 publications found

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]

SLC26A4 Gene-Disease associations (from GenCC):

• autosomal recessive nonsyndromic hearing loss 4

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, PanelApp Australia, Labcorp Genetics (formerly Invitae)
• Pendred syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae), ClinGen
• athyreosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• thyroid hypoplasia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hearing loss, autosomal recessive

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_000441.2
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-107663357-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 446451.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 167 curated pathogenic missense variants (we use a threshold of 10). The gene has 19 curated benign missense variants. Trascript score misZ: -1.7621 (below the threshold of 3.09). GenCC associations: The gene is linked to autosomal recessive nonsyndromic hearing loss 4, Pendred syndrome, athyreosis, thyroid hypoplasia, hearing loss, autosomal recessive.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.928
• PP5: Variant 7-107663358-C-G is Pathogenic according to our data. Variant chr7-107663358-C-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1018778.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SLC26A4	NM_000441.2	c.227C>G	p.Pro76Arg	missense_variant	Exon 3 of 21	ENST00000644269.2	NP_000432.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SLC26A4	ENST00000644269.2	c.227C>G	p.Pro76Arg	missense_variant	Exon 3 of 21		NM_000441.2	ENSP00000494017.1
SLC26A4	ENST00000440056.1	c.227C>G	p.Pro76Arg	missense_variant	Exon 3 of 4	4		ENSP00000394760.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Pendred syndrome;C3538946:Autosomal recessive nonsyndromic hearing loss 4 Pathogenic:1

Feb 10, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Jan 11, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has not been reported in the literature in individuals with SLC26A4-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces proline with arginine at codon 76 of the SLC26A4 protein (p.Pro76Arg). The proline residue is highly conserved and there is a moderate physicochemical difference between proline and arginine. Other missense substitutions at this codon (p.Pro76Leu and p.Pro76Ser) have been reported in individuals affected with hearing loss and enlarged vestibular aqueduct (PMID: 17718863, 17851929, 25372295, 27792752). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.20
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.61	D;D;T
Eigen	Uncertain	0.51
Eigen_PC	Uncertain	0.54
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Uncertain	0.91	.;D;D
M_CAP	Uncertain	0.097	D
MetaRNN	Pathogenic	0.93	D;D;D
MetaSVM	Uncertain	-0.028	T
MutationAssessor	Benign	1.5	L;L;.
PhyloP100		3.6
PrimateAI	Benign	0.36	T
PROVEAN	Pathogenic	-6.7	D;.;D
REVEL	Pathogenic	0.75
Sift	Uncertain	0.019	D;.;D
Sift4G	Uncertain	0.047	D;.;D
Polyphen		0.96	D;D;.
Vest4		0.58
MutPred		0.81		Gain of MoRF binding (P = 0.0025);Gain of MoRF binding (P = 0.0025);Gain of MoRF binding (P = 0.0025);
MVP		0.93
MPC		0.076
ClinPred		0.99	D
GERP RS		4.9
Varity_R		0.68
gMVP		0.83
Mutation Taster		=13/87	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1345175795; hg19: chr7-107303803;