chr5-160036781-G-C

Position:

• chr5-160036781-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The ENST00000231238.10(TTC1):​c.482G>C​(p.Arg161Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,300 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TTC1 ENST00000231238.10 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.72

Genes affected

TTC1 (HGNC:12391): (tetratricopeptide repeat domain 1) This gene encodes a protein that belongs to the tetratrico peptide repeat superfamily of proteins. The encoded protein plays a role in protein-protein interactions, and binds to the Galpha subunit of G protein-coupled receptors to activate the Ras signaling pathway. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Sep 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.932

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TTC1	NM_003314.3	c.482G>C	p.Arg161Thr	missense_variant	4/8	ENST00000231238.10	NP_003305.1
TTC1	NM_001282500.2	c.482G>C	p.Arg161Thr	missense_variant	4/8		NP_001269429.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TTC1	ENST00000231238.10	c.482G>C	p.Arg161Thr	missense_variant	4/8	1	NM_003314.3	ENSP00000231238	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461300 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 726994

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 27, 2022

The c.482G>C (p.R161T) alteration is located in exon 4 (coding exon 3) of the TTC1 gene. This alteration results from a G to C substitution at nucleotide position 482, causing the arginine (R) at amino acid position 161 to be replaced by a threonine (T). 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	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Benign	0.35	T;T
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.98	.;D
M_CAP	Pathogenic	0.33	D
MetaRNN	Pathogenic	0.93	D;D
MetaSVM	Uncertain	0.65	D
MutationAssessor	Pathogenic	4.0	H;H
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.62	T
PROVEAN	Pathogenic	-6.0	D;D
REVEL	Pathogenic	0.70
Sift	Uncertain	0.0010	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.94
MVP		0.95
MPC		0.48
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.84
gMVP		0.83

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

Other links and lift over

dbSNP: rs375255193; hg19: chr5-159463788;