9-72820980-C-A

Variant names:

• chr9-72820980-C-A
• rs767285617
• NM_138691.3:c.1902C>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP2

The NM_138691.3(TMC1):​c.1902C>A​(p.Asn634Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,886 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Synonymous variant affecting the same amino acid position (i.e. N634N) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TMC1 NM_138691.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.112
• Publications: 0 publications found

Genes affected

TMC1 (HGNC:16513): (transmembrane channel like 1) This gene is considered a member of a gene family predicted to encode transmembrane proteins. The specific function of this gene is unknown; however, it is known to be required for normal function of cochlear hair cells. Mutations in this gene have been associated with progressive postlingual hearing loss and profound prelingual deafness. [provided by RefSeq, Jul 2008]

TMC1 Gene-Disease associations (from GenCC):

• autosomal recessive nonsyndromic hearing loss 7

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics, PanelApp Australia
• nonsyndromic genetic hearing loss

  Inheritance: SD, AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen
• autosomal dominant nonsyndromic hearing loss 36

  Inheritance: AD, AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), PanelApp Australia
• autosomal dominant nonsyndromic hearing loss

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• 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 27 curated pathogenic missense variants (we use a threshold of 10). The gene has 8 curated benign missense variants. Gene score misZ: 0.85843 (below the threshold of 3.09). Trascript score misZ: 1.5687 (below the threshold of 3.09). GenCC associations: The gene is linked to nonsyndromic genetic hearing loss, autosomal recessive nonsyndromic hearing loss 7, autosomal dominant nonsyndromic hearing loss 36, hearing loss, autosomal recessive, autosomal dominant nonsyndromic hearing loss.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TMC1	NM_138691.3	c.1902C>A	p.Asn634Lys	missense_variant	Exon 20 of 24	ENST00000297784.10	NP_619636.2
TMC1	XM_017014256.2	c.1905C>A	p.Asn635Lys	missense_variant	Exon 17 of 21		XP_016869745.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TMC1	ENST00000297784.10	c.1902C>A	p.Asn634Lys	missense_variant	Exon 20 of 24	1	NM_138691.3	ENSP00000297784.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461886 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000224 AC: 1 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112004

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Benign	-0.0069	T
BayesDel_noAF	Benign	-0.25
CADD	Benign	16
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.76	D;D;.;D;.
Eigen	Benign	-0.52
Eigen_PC	Benign	-0.71
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Benign	0.82	.;.;T;T;T
M_CAP	Benign	0.033	D
MetaRNN	Uncertain	0.49	T;T;T;T;T
MetaSVM	Uncertain	-0.16	T
MutationAssessor	Pathogenic	3.2	M;M;.;M;.
PhyloP100		0.11
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-5.4	D;.;.;D;.
REVEL	Uncertain	0.42
Sift	Uncertain	0.0010	D;.;.;D;.
Sift4G	Pathogenic	0.0	D;.;.;D;.
Polyphen		0.83	P;P;.;P;.
Vest4		0.78
MutPred		0.55		Loss of catalytic residue at N634 (P = 0.0215);Loss of catalytic residue at N634 (P = 0.0215);.;Loss of catalytic residue at N634 (P = 0.0215);.;
MVP		0.74
MPC		0.55
ClinPred		1.0	D
GERP RS		-6.1
Varity_R		0.97
gMVP		0.92
Mutation Taster		=17/83	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: rs767285617; hg19: chr9-75435896;