rs762040036

chr9-95449298-C-Achr9-95449298-C-Gchr9-95449298-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_000264.5(PTCH1):c.3575G>T(p.Arg1192Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000285 in 1,401,944 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. R1192C) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000029 (0 hom.)
• Consequence: PTCH1 NM_000264.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 4.76

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, PTCH1

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PTCH1	NM_000264.5	c.3575G>T	p.Arg1192Leu	missense_variant	22/24	ENST00000331920.11
PTCH1	NM_001083603.3	c.3572G>T	p.Arg1191Leu	missense_variant	22/24	ENST00000437951.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PTCH1	ENST00000331920.11	c.3575G>T	p.Arg1192Leu	missense_variant	22/24	5	NM_000264.5	A2
PTCH1	ENST00000437951.6	c.3572G>T	p.Arg1191Leu	missense_variant	22/24	5	NM_001083603.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000285 AC: 4 AN: 1401944 Hom.: 0 Cov.: 31 AF XY: 0.00000144 AC XY: 1 AN XY: 692182

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: 0.00000277

Gnomad4 OTH exome AF: 0.0000172

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Gorlin syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 29, 2023

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 1192 of the PTCH1 protein (p.Arg1192Leu). 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: 220033). 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

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 30, 2022

The p.R1192L variant (also known as c.3575G>T), located in coding exon 22 of the PTCH1 gene, results from a G to T substitution at nucleotide position 3575. The arginine at codon 1192 is replaced by leucine, an amino acid with dissimilar properties. This alteration has been reported in an individual from a cohort of 1191 cancer index patients who underwent clinical evaluation and testing with multigene panels (Chan GHJ et al. Oncotarget, 2018 Jul;9:30649-30660). This amino acid position is highly 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	0.13
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.12
Cadd	Benign	23
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.83	D;.;.;.;.;.;.
Eigen	Benign	0.016
Eigen_PC	Benign	0.12
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;.;D;D;.;.;D
M_CAP	Uncertain	0.28	D
MetaRNN	Uncertain	0.55	D;D;D;D;D;D;D
MetaSVM	Uncertain	0.20	D
MutationAssessor	Uncertain	2.3	M;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.59	T
PROVEAN	Uncertain	-4.0	D;D;D;D;D;D;D
REVEL	Uncertain	0.54
Sift	Uncertain	0.0020	D;D;D;D;D;D;D
Sift4G	Uncertain	0.039	D;D;D;D;D;D;D
Polyphen		0.22	B;.;.;B;B;.;B
Vest4		0.66
MutPred		0.27		Gain of glycosylation at S1197 (P = 0.0728);.;.;.;.;.;.;
MVP		0.90
MPC		0.76
ClinPred		0.99	D
GERP RS		4.9
Varity_R		0.61
gMVP		0.90

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: rs762040036; hg19: chr9-98211580;