NM_000441.2:c.1919G>T

Variant names:

• chr7-107701942-G-T
• rs786204502
• NM_000441.2:c.1919G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2 PM5 PP2 PP3_Moderate

The NM_000441.2(SLC26A4):​c.1919G>T​(p.Trp640Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,460,958 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. W640C) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SLC26A4 NM_000441.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 8.46
• Publications: 2 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: Likely_pathogenic. The variant received 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-107701943-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 504676.
• 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, 0.891

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SLC26A4	NM_000441.2	c.1919G>T	p.Trp640Leu	missense_variant	Exon 17 of 21	ENST00000644269.2	NP_000432.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SLC26A4	ENST00000644269.2	c.1919G>T	p.Trp640Leu	missense_variant	Exon 17 of 21		NM_000441.2	ENSP00000494017.1
SLC26A4	ENST00000492030.2	n.206G>T		non_coding_transcript_exon_variant	Exon 2 of 6	5
SLC26A4	ENST00000644846.1	n.629G>T		non_coding_transcript_exon_variant	Exon 7 of 10			ENSP00000494344.1
SLC26A4	ENST00000480841.5	n.*58G>T		downstream_gene_variant		3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1460958 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 726858

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000299 AC: 1 AN: 33460

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39686

South Asian (SAS) AF: 0.00 AC: 0 AN: 86240

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111198

Other (OTH) AF: 0.00 AC: 0 AN: 60344

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.19
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.59	D;D
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	.;D
M_CAP	Uncertain	0.28	D
MetaRNN	Pathogenic	0.89	D;D
MetaSVM	Uncertain	0.78	D
MutationAssessor	Benign	1.6	L;L
PhyloP100		8.5
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-10	D;.
REVEL	Pathogenic	0.75
Sift	Benign	0.079	T;.
Sift4G	Benign	0.11	T;.
Polyphen		1.0	D;D
Vest4		0.69
MutPred		0.53		Gain of disorder (P = 0.0405);Gain of disorder (P = 0.0405);
MVP		0.99
MPC		0.074
ClinPred		1.0	D
GERP RS		5.8
Varity_R		0.83
gMVP		0.70
Mutation Taster		=8/92	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: rs786204502; hg19: chr7-107342387;