chr2-46994386-G-T

Variant names:

• chr2-46994386-G-T
• rs113997845
• NM_020458.4:c.873G>T

Variant summary

Our verdict is Benign. The variant received -9 ACMG points: 2P and 11B. PM2 BP4_Moderate BP6_Very_Strong BP7

The NM_020458.4(TTC7A):​c.873G>T​(p.Leu291Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,613,664 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. L291L) has been classified as Benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TTC7A NM_020458.4 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: 0.796
• Publications: 1 publications found

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 Gene-Disease associations (from GenCC):

• gastrointestinal defects and immunodeficiency syndrome 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• multiple intestinal atresia

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, Ambry Genetics

ACMG classification

Our verdict: Benign. The variant received -9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.46).
• BP6: Variant 2-46994386-G-T is Benign according to our data. Variant chr2-46994386-G-T is described in ClinVar as Likely_benign. ClinVar VariationId is 1588526.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.796 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020458.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTC7A	NM_020458.4	MANE Select	c.873G>T	p.Leu291Leu	synonymous	Exon 7 of 20	NP_065191.2
	TTC7A	NM_001288951.2		c.873G>T	p.Leu291Leu	synonymous	Exon 7 of 21	NP_001275880.1
	TTC7A	NM_001288953.2		c.771G>T	p.Leu257Leu	synonymous	Exon 8 of 21	NP_001275882.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTC7A	ENST00000319190.11	TSL:2 MANE Select	c.873G>T	p.Leu291Leu	synonymous	Exon 7 of 20	ENSP00000316699.5
	TTC7A	ENST00000394850.6	TSL:1	c.873G>T	p.Leu291Leu	synonymous	Exon 7 of 21	ENSP00000378320.2
	TTC7A	ENST00000409825.5	TSL:1	n.*622G>T		non_coding_transcript_exon	Exon 8 of 21	ENSP00000386521.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152162 Hom.: 0 Cov.: 32

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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461502 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727040

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44684

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26092

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86226

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53382

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111810

Other (OTH) AF: 0.00 AC: 0 AN: 60378

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152162 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74326

African (AFR) AF: 0.00 AC: 0 AN: 41434

American (AMR) AF: 0.00 AC: 0 AN: 15272

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5198

South Asian (SAS) AF: 0.00 AC: 0 AN: 4836

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68020

Other (OTH) AF: 0.00 AC: 0 AN: 2090

ClinVar

Significance: Likely benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

TTC7A-related disorder Benign:1

Oct 08, 2021

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications).

not provided Benign:1

Breakthrough Genomics, Breakthrough Genomics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: not provided

Multiple gastrointestinal atresias Benign:1

Nov 11, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.46
CADD	Benign	8.9
DANN	Benign	0.82
PhyloP100		0.80
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=99/1	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: rs113997845; hg19: chr2-47221525;