chr9-95447004-C-A

Variant names:

• chr9-95447004-C-A
• rs369882883
• NM_000264.5:c.4252G>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000264.5(PTCH1):​c.4252G>T​(p.Val1418Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. V1418I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: PTCH1 NM_000264.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.01
• Publications: 5 publications found

Genes affected

PTCH1 (HGNC:9585): (patched 1) This gene encodes a member of the patched family of proteins and a component of the hedgehog signaling pathway. Hedgehog signaling is important in embryonic development and tumorigenesis. The encoded protein is the receptor for the secreted hedgehog ligands, which include sonic hedgehog, indian hedgehog and desert hedgehog. Following binding by one of the hedgehog ligands, the encoded protein is trafficked away from the primary cilium, relieving inhibition of the G-protein-coupled receptor smoothened, which results in activation of downstream signaling. Mutations of this gene have been associated with basal cell nevus syndrome and holoprosencephaly. [provided by RefSeq, Aug 2017]

PTCH1 Gene-Disease associations (from GenCC):

• basal cell nevus syndrome 1

  Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
• holoprosencephaly 7

  Inheritance: AD Classification: DEFINITIVE, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• nevoid basal cell carcinoma syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, ClinGen, Labcorp Genetics (formerly Invitae), Orphanet
• holoprosencephaly

  Inheritance: AD Classification: LIMITED Submitted by: Illumina

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PTCH1	NM_000264.5	c.4252G>T	p.Val1418Phe	missense_variant	Exon 23 of 24	ENST00000331920.11	NP_000255.2
PTCH1	NM_001083603.3	c.4249G>T	p.Val1417Phe	missense_variant	Exon 23 of 24	ENST00000437951.6	NP_001077072.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PTCH1	ENST00000331920.11	c.4252G>T	p.Val1418Phe	missense_variant	Exon 23 of 24	5	NM_000264.5	ENSP00000332353.6
PTCH1	ENST00000437951.6	c.4249G>T	p.Val1417Phe	missense_variant	Exon 23 of 24	5	NM_001083603.3	ENSP00000389744.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461882 Hom.: 0 Cov.: 30 AF XY: 0.00000413 AC XY: 3 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

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: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

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

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1112012

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Gorlin syndrome Uncertain:1

May 08, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces valine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 1418 of the PTCH1 protein (p.Val1418Phe). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with PTCH1-related conditions. ClinVar contains an entry for this variant (Variation ID: 861688). 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 PTCH1 protein function with a negative predictive value of 95%. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Mar 06, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.V1418F variant (also known as c.4252G>T), located in coding exon 23 of the PTCH1 gene, results from a G to T substitution at nucleotide position 4252. The valine at codon 1418 is replaced by phenylalanine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.085
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Uncertain	-0.080
CADD	Benign	18
DANN	Uncertain	1.0
DEOGEN2	Benign	0.29	T;.;.;.;.;.;.
Eigen	Benign	-0.079
Eigen_PC	Benign	-0.093
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.90	D;.;D;D;.;.;D
M_CAP	Uncertain	0.15	D
MetaRNN	Uncertain	0.43	T;T;T;T;T;T;T
MetaSVM	Uncertain	0.22	D
MutationAssessor	Benign	1.8	L;.;.;.;.;.;.
PhyloP100		2.0
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	-0.50	N;N;N;N;N;N;N
REVEL	Uncertain	0.37
Sift	Uncertain	0.014	D;D;D;D;D;D;D
Sift4G	Uncertain	0.034	D;D;D;D;D;D;D
Polyphen		0.90	P;.;.;P;P;.;P
Vest4		0.60
MutPred		0.48		Loss of sheet (P = 0.0315);.;.;.;.;.;.;
MVP		0.48
MPC		0.16
ClinPred		0.65	D
GERP RS		4.2
Varity_R		0.14
gMVP		0.63
Mutation Taster		=77/23	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: rs369882883; hg19: chr9-98209286; COSMIC: COSV59487074;