7-107701970-C-G

Variant names:

• chr7-107701970-C-G
• NM_000441.2:c.1947C>G
• SLC26A4 p.Asn649Lys

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 5P and 1B. PM1 PM2 PP2 BP4

The NM_000441.2(SLC26A4):​c.1947C>G​(p.Asn649Lys) 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 benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. N649N) has been classified as Likely benign. The gene SLC26A4 is included in the ClinGen Criteria Specification Registry.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SLC26A4 NM_000441.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.526
• Publications: 0 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, Labcorp Genetics (formerly Invitae), PanelApp Australia
• 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

Specifications for SLC26A4 are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM1: In a hotspot region, there are 3 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
• 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 hearing loss, autosomal recessive, Pendred syndrome, autosomal recessive nonsyndromic hearing loss 4, thyroid hypoplasia, athyreosis.
• BP4: Computational evidence support a benign effect (MetaRNN=0.30429575).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000441.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SLC26A4	NM_000441.2	MANE Select	c.1947C>G	p.Asn649Lys	missense	Exon 17 of 21	NP_000432.1	O43511-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SLC26A4	ENST00000644269.2	MANE Select	c.1947C>G	p.Asn649Lys	missense	Exon 17 of 21	ENSP00000494017.1	O43511-1
	SLC26A4	ENST00000888701.1		c.1947C>G	p.Asn649Lys	missense	Exon 16 of 20	ENSP00000558760.1
	SLC26A4	ENST00000888700.1		c.1869C>G	p.Asn623Lys	missense	Exon 16 of 20	ENSP00000558759.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Uncertain	0.017	T
BayesDel_noAF	Benign	-0.21
CADD	Benign	15
DANN	Uncertain	0.99
DEOGEN2	Benign	0.32	T
Eigen	Benign	-0.14
Eigen_PC	Benign	-0.067
FATHMM_MKL	Benign	0.70	D
LIST_S2	Benign	0.65	T
M_CAP	Uncertain	0.15	D
MetaRNN	Benign	0.30	T
MetaSVM	Uncertain	0.36	D
MutationAssessor	Benign	1.4	L
PhyloP100		0.53
PrimateAI	Uncertain	0.54	T
PROVEAN	Benign	-1.8	N
REVEL	Uncertain	0.46
Sift	Benign	0.47	T
Sift4G	Benign	0.68	T
Varity_R		0.14
gMVP		0.48
Mutation Taster		=49/51	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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr7-107342415;