rs1554698288

Positions:

• chr9-95476815-A-C

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_000264.5(PTCH1):​c.1546T>G​(p.Phe516Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,784 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PTCH1 NM_000264.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:1
• Conservation: PhyloP100: 8.73

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 Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 11 uncertain in NM_000264.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, PTCH1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.971

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PTCH1	NM_000264.5	c.1546T>G	p.Phe516Val	missense_variant	11/24	ENST00000331920.11
PTCH1	NM_001083603.3	c.1543T>G	p.Phe515Val	missense_variant	11/24	ENST00000437951.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PTCH1	ENST00000331920.11	c.1546T>G	p.Phe516Val	missense_variant	11/24	5	NM_000264.5	A2
PTCH1	ENST00000437951.6	c.1543T>G	p.Phe515Val	missense_variant	11/24	5	NM_001083603.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461784 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727186

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

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Basal cell carcinoma, susceptibility to, 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

May 02, 2023

- -

Gorlin syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 21, 2023

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. 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 expected to disrupt PTCH1 protein function. ClinVar contains an entry for this variant (Variation ID: 524593). This variant has not been reported in the literature in individuals affected with PTCH1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces phenylalanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 516 of the PTCH1 protein (p.Phe516Val). -

Gorlin syndrome;C1835820:Holoprosencephaly 7;C2751544:Basal cell carcinoma, susceptibility to, 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Dec 08, 2021

- -

Hereditary cancer-predisposing syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 03, 2023

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.89	D;.;.;.;.;.;.;.
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.84	T;.;T;T;.;.;T;D
M_CAP	Pathogenic	0.50	D
MetaRNN	Pathogenic	0.97	D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.92	D
MutationAssessor	Pathogenic	3.3	M;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-6.5	D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.0030	D;D;D;D;D;D;D;.
Polyphen		1.0	D;D;D;D;D;D;D;.
Vest4		0.93
MutPred		0.87		Loss of catalytic residue at F516 (P = 0.0874);.;.;.;.;.;.;.;
MVP		0.84
MPC		1.7
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.95
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: rs1554698288; hg19: chr9-98239097;