2-47021918-G-C

Variant names:

• chr2-47021918-G-C
• NM_020458.4:c.1449G>C
• TTC7A p.Gly483Gly

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_020458.4(TTC7A):​c.1449G>C​(p.Gly483Gly) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. G483G) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TTC7A NM_020458.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.0990
• 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: G2P, Labcorp Genetics (formerly Invitae)
• multiple intestinal atresia

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

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.51).
• BP7: Synonymous conserved (PhyloP=0.099 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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTC7A	NM_020458.4	MANE Select	c.1449G>C	p.Gly483Gly	synonymous	Exon 12 of 20	NP_065191.2	Q9ULT0-1
	TTC7A	NM_001288951.2		c.1449G>C	p.Gly483Gly	synonymous	Exon 12 of 21	NP_001275880.1	Q9ULT0-4
	TTC7A	NM_001288953.2		c.1347G>C	p.Gly449Gly	synonymous	Exon 13 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.1449G>C	p.Gly483Gly	synonymous	Exon 12 of 20	ENSP00000316699.5	Q9ULT0-1
	TTC7A	ENST00000394850.6	TSL:1	c.1449G>C	p.Gly483Gly	synonymous	Exon 12 of 21	ENSP00000378320.2	Q9ULT0-4
	TTC7A	ENST00000409825.5	TSL:1	n.*1198G>C		non_coding_transcript_exon	Exon 13 of 21	ENSP00000386521.1	H0Y3V7

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.51
CADD	Benign	6.2
DANN	Benign	0.66
PhyloP100		0.099
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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr2-47249057;