rs878853857

chr9-95449930-C-Gchr9-95449930-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_000264.5(PTCH1):c.3460G>C(p.Ala1154Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 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. A1154G) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: PTCH1 NM_000264.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.86

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 7 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 12 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, 0.859

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PTCH1	NM_000264.5	c.3460G>C	p.Ala1154Pro	missense_variant	21/24	ENST00000331920.11
PTCH1	NM_001083603.3	c.3457G>C	p.Ala1153Pro	missense_variant	21/24	ENST00000437951.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PTCH1	ENST00000331920.11	c.3460G>C	p.Ala1154Pro	missense_variant	21/24	5	NM_000264.5	A2
PTCH1	ENST00000437951.6	c.3457G>C	p.Ala1153Pro	missense_variant	21/24	5	NM_001083603.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

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

Jan 01, 2016

Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a PTCH1-related disease. In summary, this is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. This sequence change replaces alanine with proline at codon 1154 of the PTCH1 protein (p.Ala1154Pro). The alanine residue is highly conserved and there is a small physicochemical difference between alanine and proline. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jan 22, 2020

Not observed in large population cohorts (Lek 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.33
Cadd	Pathogenic	27
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.68	D;.;.;.;.;.;.
Eigen	Pathogenic	0.73
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	D;.;D;D;.;.;D
M_CAP	Uncertain	0.097	D
MetaRNN	Pathogenic	0.86	D;D;D;D;D;D;D
MetaSVM	Uncertain	0.42	D
MutationAssessor	Benign	1.4	L;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.85	D
PROVEAN	Benign	-2.0	N;N;N;N;N;N;N
REVEL	Pathogenic	0.81
Sift	Benign	0.20	T;T;T;T;T;T;T
Sift4G	Benign	0.20	T;T;T;T;T;T;T
Polyphen		1.0	D;.;.;D;D;.;D
Vest4		0.92
MutPred		0.68		Loss of catalytic residue at A1154 (P = 0.0235);.;.;.;.;.;.;
MVP		0.79
MPC		1.4
ClinPred		0.94	D
GERP RS		5.5
Varity_R		0.91
gMVP		0.96

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs878853857; hg19: chr9-98212212;