rs886037747

Variant names:

• chr2-46950490-TTATC-T
• rs886037747
• NM_020458.4:c.315_318delTCTA

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_020458.4(TTC7A):​c.315_318delTCTA​(p.Tyr105fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,884 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. Y105Y) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TTC7A NM_020458.4 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 2.41
• Publications: 0 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: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-46950490-TTATC-T is Pathogenic according to our data. Variant chr2-46950490-TTATC-T is described in ClinVar as Pathogenic. ClinVar VariationId is 190390.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTC7A	NM_020458.4	MANE Select	c.315_318delTCTA	p.Tyr105fs	frameshift	Exon 2 of 20	NP_065191.2	Q9ULT0-1
	TTC7A	NM_001288951.2		c.315_318delTCTA	p.Tyr105fs	frameshift	Exon 2 of 21	NP_001275880.1	Q9ULT0-4
	TTC7A	NM_001288953.2		c.213_216delTCTA	p.Tyr71fs	frameshift	Exon 3 of 21	NP_001275882.1	G5E9G4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTC7A	ENST00000319190.11	TSL:2 MANE Select	c.315_318delTCTA	p.Tyr105fs	frameshift	Exon 2 of 20	ENSP00000316699.5	Q9ULT0-1
	TTC7A	ENST00000394850.6	TSL:1	c.315_318delTCTA	p.Tyr105fs	frameshift	Exon 2 of 21	ENSP00000378320.2	Q9ULT0-4
	TTC7A	ENST00000409825.5	TSL:1	n.72_75delTCTA		non_coding_transcript_exon	Exon 1 of 21	ENSP00000386521.1	H0Y3V7

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461884 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 727238

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: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
2	-	-	Gastrointestinal defects and immunodeficiency syndrome 1 (2)
1	-	-	Multiple gastrointestinal atresias (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.4
Mutation Taster		=1/199	disease causing (ClinVar)

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: rs886037747; hg19: chr2-47177629;