chr9-95508348-C-G

Position:

• chr9-95508348-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_000264.5(PTCH1):​c.14G>C​(p.Gly5Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000135 in 148,084 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000014 (0 hom., cov: 32)
  • Exomes 𝑓: 9.4e-7 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PTCH1 NM_000264.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:1
• Conservation: PhyloP100: 0.128

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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), PTCH1. . Gene score misZ 1.6774 (greater than the threshold 3.09). Trascript score misZ 3.1343 (greater than threshold 3.09). GenCC has associacion of gene with holoprosencephaly 7, nevoid basal cell carcinoma syndrome, holoprosencephaly.
• BP4: Computational evidence support a benign effect (MetaRNN=0.11069116).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PTCH1	NM_000264.5	c.14G>C	p.Gly5Ala	missense_variant	1/24	ENST00000331920.11	NP_000255.2
PTCH1	NM_001083603.3	c.199-1749G>C		intron_variant		ENST00000437951.6	NP_001077072.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PTCH1	ENST00000331920.11	c.14G>C	p.Gly5Ala	missense_variant	1/24	5	NM_000264.5	ENSP00000332353	A2
PTCH1	ENST00000437951.6	c.199-1749G>C		intron_variant		5	NM_001083603.3	ENSP00000389744

Frequencies

GnomAD3 genomes AF: 0.0000135 AC: 2 AN: 148084 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000248

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000150

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 9.40e-7 AC: 1 AN: 1063572 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 505024

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: 0.00000110

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000135 AC: 2 AN: 148084 Hom.: 0 Cov.: 32 AF XY: 0.0000277 AC XY: 2 AN XY: 72230

Gnomad4 AFR AF: 0.0000248

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000150

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000113

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Dec 28, 2023	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jun 08, 2023	This variant has not been reported in the published literature. The frequency of this variant in the general population, 0.000018 (2/112980 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the assessment of its pathogenicity. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is benign. Based on the available information, we are unable to determine the clinical significance of this variant. -

Basal cell carcinoma, susceptibility to, 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Sep 13, 2023

- -

Gorlin syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 18, 2023

This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 5 of the PTCH1 protein (p.Gly5Ala). 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: 221148). 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 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 17, 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	Benign	0.068
BayesDel_addAF	Benign	-0.12	T
BayesDel_noAF	Benign	-0.41
CADD	Benign	17
DANN	Benign	0.83
DEOGEN2	Benign	0.20	T
Eigen	Benign	-0.83
Eigen_PC	Benign	-0.62
FATHMM_MKL	Benign	0.33	N
LIST_S2	Benign	0.67	T
M_CAP	Pathogenic	0.98	D
MetaRNN	Benign	0.11	T
MetaSVM	Benign	-0.67	T
MutationAssessor	Benign	0.0	N
MutationTaster	Benign	1.0	D;D;D;D;N
PrimateAI	Pathogenic	0.89	D
PROVEAN	Benign	-0.47	N
REVEL	Uncertain	0.34
Sift	Benign	1.0	T
Sift4G	Benign	1.0	T
Polyphen		0.0	B
Vest4		0.059
MutPred		0.085		Loss of loop (P = 0.0112);
MVP		0.42
MPC		1.3
ClinPred		0.062	T
GERP RS		1.9
Varity_R		0.056
gMVP		0.47

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: rs864622762; hg19: chr9-98270630;