15-43600197-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_153700.2(STRC):c.5090C>T(p.Ala1697Val) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000864 in 1,273,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 22)
  • Exomes 𝑓: 0.0000086 (0 hom.)
• Consequence: STRC NM_153700.2 missense, splice_region
• Scores: Splicing: ADA: 0.001310
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.82

Genes affected

STRC (HGNC:16035): (stereocilin) This gene encodes a protein that is associated with the hair bundle of the sensory hair cells in the inner ear. The hair bundle is composed of stiff microvilli called stereocilia and is involved with mechanoreception of sound waves. This gene is part of a tandem duplication on chromosome 15; the second copy is a pseudogene. Mutations in this gene cause autosomal recessive non-syndromic deafness. [provided by RefSeq, Jul 2008]

CKMT1B (HGNC:1995): (creatine kinase, mitochondrial 1B) Mitochondrial creatine (MtCK) kinase is responsible for the transfer of high energy phosphate from mitochondria to the cytosolic carrier, creatine. It belongs to the creatine kinase isoenzyme family. It exists as two isoenzymes, sarcomeric MtCK and ubiquitous MtCK, encoded by separate genes. Mitochondrial creatine kinase occurs in two different oligomeric forms: dimers and octamers, in contrast to the exclusively dimeric cytosolic creatine kinase isoenzymes. Many malignant cancers with poor prognosis have shown overexpression of ubiquitous mitochondrial creatine kinase; this may be related to high energy turnover and failure to eliminate cancer cells via apoptosis. Ubiquitous mitochondrial creatine kinase has 80% homology with the coding exons of sarcomeric mitochondrial creatine kinase. Two genes located near each other on chromosome 15 have been identified which encode identical mitochondrial creatine kinase proteins. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.33108425).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
STRC	NM_153700.2	c.5090C>T	p.Ala1697Val	missense_variant, splice_region_variant	27/29	ENST00000450892.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
STRC	ENST00000450892.7	c.5090C>T	p.Ala1697Val	missense_variant, splice_region_variant	27/29	5	NM_153700.2	P2

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD3 exomes AF: 0.0000134 AC: 2 AN: 149220 Hom.: 0 AF XY: 0.0000251 AC XY: 2 AN XY: 79668

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000876

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000864 AC: 11 AN: 1273816 Hom.: 0 Cov.: 18 AF XY: 0.0000110 AC XY: 7 AN XY: 636568

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000129

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000185

GnomAD4 genome Cov.: 22

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 30, 2021

The c.5090C>T (p.A1697V) alteration is located in exon 27 (coding exon 27) of the STRC gene. This alteration results from a C to T substitution at nucleotide position 5090, causing the alanine (A) at amino acid position 1697 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.31
BayesDel_addAF	Benign	-0.10	T
BayesDel_noAF	Benign	-0.19
Cadd	Uncertain	23
Dann	Uncertain	0.99
DEOGEN2	Benign	0.30	T;.
Eigen	Benign	-0.11
Eigen_PC	Benign	-0.13
FATHMM_MKL	Benign	0.73	D
LIST_S2	Benign	0.69	T;T
M_CAP	Uncertain	0.20	D
MetaRNN	Benign	0.33	T;T
MetaSVM	Uncertain	-0.12	T
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.53	T
PROVEAN	Benign	-2.1	N;N
REVEL	Uncertain	0.49
Sift	Uncertain	0.025	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.22
MutPred		0.33		Gain of sheet (P = 0.0827);.;
MVP		0.65
ClinPred		0.59	D
GERP RS		3.0
Varity_R		0.066
gMVP		0.44

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0013
dbscSNV1_RF	Benign	0.084
SpliceAI score (max)		0.080		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs1397103328; hg19: chr15-43892395;