rs146284515

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2BP4_StrongBS1_Supporting

The NM_020458.4(TTC7A):c.1189G>A(p.Val397Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000132 in 1,613,746 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V397D) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00016 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00013 ( 0 hom. )

Consequence

TTC7A
NM_020458.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 4.68

Variant links:

Genes affected

TTC7A (HGNC:19750): (tetratricopeptide repeat domain 7A) This gene encodes a protein containing tetratricopeptide repeats. Mutations in this gene disrupt intestinal development and can cause early onset inflammatory bowel disease and intestinal atresia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jun 2014]

TTC7A links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.031164825).

BS1

Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.000158 (24/152188) while in subpopulation EAS AF= 0.00116 (6/5164). AF 95% confidence interval is 0.000506. There are 0 homozygotes in gnomad4. There are 14 alleles in male gnomad4 subpopulation. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTC7A	NM_020458.4 linkuse as main transcript	c.1189G>A	p.Val397Ile	missense_variant	9/20	ENST00000319190.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTC7A	ENST00000319190.11 linkuse as main transcript	c.1189G>A	p.Val397Ile	missense_variant	9/20	2	NM_020458.4	P1	Q9ULT0-1

Frequencies

GnomAD3 genomes

AF:

0.000151

AC:

AN:

152070

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000966

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000966

Gnomad SAS

AF:

0.000624

Gnomad FIN

AF:

0.000188

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000132

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000187

AC:

AN:

251114

Hom.:

AF XY:

0.000170

AC XY:

AN XY:

135684

show subpopulations

Gnomad AFR exome

AF:

0.000123

Gnomad AMR exome

AF:

0.000145

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00109

Gnomad SAS exome

AF:

0.000261

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000880

Gnomad OTH exome

AF:

0.000326

GnomAD4 exome

AF:

0.000129

AC:

189

AN:

1461558

Hom.:

Cov.:

AF XY:

0.000140

AC XY:

102

AN XY:

727036

show subpopulations

Gnomad4 AFR exome

AF:

0.0000597

Gnomad4 AMR exome

AF:

0.000112

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00156

Gnomad4 SAS exome

AF:

0.000336

Gnomad4 FIN exome

AF:

0.000188

Gnomad4 NFE exome

AF:

0.0000450

Gnomad4 OTH exome

AF:

0.000513

GnomAD4 genome

AF:

0.000158

AC:

AN:

152188

Hom.:

Cov.:

AF XY:

0.000188

AC XY:

AN XY:

74428

show subpopulations

Gnomad4 AFR

AF:

0.0000963

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00116

Gnomad4 SAS

AF:

0.000624

Gnomad4 FIN

AF:

0.000188

Gnomad4 NFE

AF:

0.000132

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000915

Hom.:

Bravo

AF:

0.000151

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.000206

AC:

Asia WGS

AF:

0.00202

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Multiple gastrointestinal atresias

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Jun 21, 2019	This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jan 18, 2024	This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 397 of the TTC7A protein (p.Val397Ile). This variant is present in population databases (rs146284515, gnomAD 0.1%). This variant has not been reported in the literature in individuals affected with TTC7A-related conditions. ClinVar contains an entry for this variant (Variation ID: 572873). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt TTC7A protein function with a negative predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 31, 2022

The c.1189G>A (p.V397I) alteration is located in exon 9 (coding exon 9) of the TTC7A gene. This alteration results from a G to A substitution at nucleotide position 1189, causing the valine (V) at amino acid position 397 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Mayo Clinic Laboratories, Mayo Clinic

Aug 11, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.088

BayesDel_addAF

Benign

-0.45

BayesDel_noAF

Benign

-0.47

Cadd

Benign

Dann

Benign

0.97

Eigen

Benign

-0.42

Eigen_PC

Benign

-0.35

FATHMM_MKL

Uncertain

0.90

LIST_S2

Benign

0.17

T;T;T

M_CAP

Benign

0.013

MetaRNN

Benign

0.031

T;T;T

MetaSVM

Benign

-1.1

MutationTaster

Benign

1.0

N;N;N;N

PrimateAI

Benign

0.30

PROVEAN

Benign

-0.75

N;N;N

REVEL

Benign

0.090

Sift

Benign

0.16

T;T;T

Sift4G

Benign

0.13

T;T;T

Polyphen

0.15

B;P;.

Vest4

0.28

MVP

0.33

MPC

0.078

ClinPred

0.024

GERP RS

3.9

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.039

gMVP

0.12

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

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