chr9-72788378-C-A

Variant names:

• chr9-72788378-C-A
• rs113342704
• NM_138691.3:c.924C>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_138691.3(TMC1):​c.924C>A​(p.Asp308Glu) 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 1,461,768 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. 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 Likely benign in ClinVar. Synonymous variant affecting the same amino acid position (i.e. D308D) 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: 0.190
• Publications: 2 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 1 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.
• BP4: Computational evidence support a benign effect (MetaRNN=0.10783756).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TMC1	NM_138691.3	c.924C>A	p.Asp308Glu	missense_variant	Exon 14 of 24	ENST00000297784.10	NP_619636.2
TMC1	XM_017014256.2	c.927C>A	p.Asp309Glu	missense_variant	Exon 11 of 21		XP_016869745.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TMC1	ENST00000297784.10	c.924C>A	p.Asp308Glu	missense_variant	Exon 14 of 24	1	NM_138691.3	ENSP00000297784.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251418 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

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: 1461768 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727180

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

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

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39686

South Asian (SAS) AF: 0.00 AC: 0 AN: 86250

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: 1111930

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Benign	-0.34	T
BayesDel_noAF	Benign	-0.56
CADD	Benign	17
DANN	Benign	0.97
DEOGEN2	Benign	0.16	T;T;.;T;.
Eigen	Benign	-0.69
Eigen_PC	Benign	-0.51
FATHMM_MKL	Benign	0.76	D
LIST_S2	Benign	0.71	.;.;T;T;T
M_CAP	Benign	0.0082	T
MetaRNN	Benign	0.11	T;T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.57	N;N;.;N;.
PhyloP100		0.19
PrimateAI	Uncertain	0.66	T
PROVEAN	Benign	-0.89	N;.;.;N;.
REVEL	Benign	0.11
Sift	Benign	0.21	T;.;.;T;.
Sift4G	Benign	0.60	T;.;.;T;.
Polyphen		0.0020	B;B;.;B;.
Vest4		0.30
MutPred		0.22		Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);.;Loss of sheet (P = 0.0817);.;
MVP		0.11
MPC		0.16
ClinPred		0.19	T
GERP RS		4.0
Varity_R		0.12
gMVP		0.61
Mutation Taster		=59/41	polymorphism

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: rs113342704; hg19: chr9-75403294;