1-54731487-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_004623.5(TTC4):c.683C>T(p.Ala228Val) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000235 in 1,613,828 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/23 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: 𝑓 0.000020 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000024 ( 1 hom. )

Consequence

TTC4
NM_004623.5 missense, splice_region

Scores

Splicing: ADA: 0.001243

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.78

Variant links:

Genes affected

TTC4 (HGNC:12394): (tetratricopeptide repeat domain 4) This gene encodes a protein that contains tetratricopeptide (TPR) repeats, which often mediate protein-protein interactions and chaperone activity. The encoded protein interacts with heat shock proteins 70 and 90. Alternative splicing results in multiple transcript variants. Naturally-occuring readthrough transcription occurs from upstream gene MROH (maestro heat-like repeat family member 7) to this gene. [provided by RefSeq, Apr 2014]

TTC4 links:

MROH7-TTC4 (HGNC:):

MROH7-TTC4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.058076292).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTC4	NM_004623.5 linkuse as main transcript	c.683C>T	p.Ala228Val	missense_variant, splice_region_variant	7/10	ENST00000371281.4
MROH7-TTC4	NR_037639.2 linkuse as main transcript	n.4861C>T		splice_region_variant, non_coding_transcript_exon_variant	30/33

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTC4	ENST00000371281.4 linkuse as main transcript	c.683C>T	p.Ala228Val	missense_variant, splice_region_variant	7/10	1	NM_004623.5	P1
TTC4	ENST00000371284.9 linkuse as main transcript	n.849C>T		splice_region_variant, non_coding_transcript_exon_variant	7/10	5

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152174

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000621

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000439

AC:

AN:

250534

Hom.:

AF XY:

0.0000739

AC XY:

AN XY:

135374

show subpopulations

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:

0.000360

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000239

AC:

AN:

1461536

Hom.:

Cov.:

AF XY:

0.0000426

AC XY:

AN XY:

727080

show subpopulations

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:

0.000371

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152292

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74464

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000622

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ExAC

AF:

0.0000494

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 12, 2021

The c.683C>T (p.A228V) alteration is located in exon 7 (coding exon 7) of the TTC4 gene. This alteration results from a C to T substitution at nucleotide position 683, causing the alanine (A) at amino acid position 228 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

0.10

BayesDel_addAF

Benign

-0.33

BayesDel_noAF

Benign

-0.41

Cadd

Benign

Dann

Uncertain

0.99

DEOGEN2

Benign

0.010

Eigen

Benign

-0.065

Eigen_PC

Benign

0.032

FATHMM_MKL

Uncertain

0.88

LIST_S2

Benign

0.74

M_CAP

Benign

0.0058

MetaRNN

Benign

0.058

MetaSVM

Benign

-1.1

MutationAssessor

Uncertain

2.4

MutationTaster

Benign

0.79

N;N

PrimateAI

Benign

0.37

PROVEAN

Benign

-1.3

REVEL

Benign

0.14

Sift

Benign

0.32

Sift4G

Benign

0.27

Polyphen

0.17

Vest4

0.13

MVP

0.42

MPC

0.050

ClinPred

0.098

GERP RS

4.0

Varity_R

0.094

gMVP

0.28

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.0012

dbscSNV1_RF

Benign

0.10

SpliceAI score (max)

0.060

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over