chr9-95446992-T-C

Position:

• chr9-95446992-T-C

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.4264A>G​(p.Arg1422Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,876 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: PTCH1 NM_000264.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.18

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=0.15696001).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PTCH1	NM_000264.5	c.4264A>G	p.Arg1422Gly	missense_variant	23/24	ENST00000331920.11	NP_000255.2
PTCH1	NM_001083603.3	c.4261A>G	p.Arg1421Gly	missense_variant	23/24	ENST00000437951.6	NP_001077072.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PTCH1	ENST00000331920.11	c.4264A>G	p.Arg1422Gly	missense_variant	23/24	5	NM_000264.5	ENSP00000332353	A2
PTCH1	ENST00000437951.6	c.4261A>G	p.Arg1421Gly	missense_variant	23/24	5	NM_001083603.3	ENSP00000389744

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251440 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135904

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461876 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727238

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Gorlin syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 26, 2022

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 not expected to disrupt PTCH1 protein function. ClinVar contains an entry for this variant (Variation ID: 453890). This variant has not been reported in the literature in individuals affected with PTCH1-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.0009%). This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 1422 of the PTCH1 protein (p.Arg1422Gly). -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Nov 15, 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 -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 04, 2022

The p.R1422G variant (also known as c.4264A>G), located in coding exon 23 of the PTCH1 gene, results from an A to G substitution at nucleotide position 4264. The arginine at codon 1422 is replaced by glycine, an amino acid with dissimilar properties. This amino acid position is conserved. 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	0.087
BayesDel_addAF	Uncertain	0.083	D
BayesDel_noAF	Benign	-0.12
CADD	Benign	20
DANN	Uncertain	0.99
DEOGEN2	Benign	0.23	T;.;.;.;.;.;.
Eigen	Benign	-0.063
Eigen_PC	Benign	0.071
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Uncertain	0.92	D;.;D;D;.;.;D
M_CAP	Uncertain	0.087	D
MetaRNN	Benign	0.16	T;T;T;T;T;T;T
MetaSVM	Uncertain	0.078	D
MutationAssessor	Benign	1.8	L;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	-0.28	N;N;N;N;N;N;N
REVEL	Uncertain	0.38
Sift	Benign	0.11	T;T;T;T;T;T;T
Sift4G	Benign	0.35	T;T;T;T;T;T;T
Polyphen		0.28	B;.;.;B;B;.;B
Vest4		0.30
MutPred		0.30		Gain of sheet (P = 0.0477);.;.;.;.;.;.;
MVP		0.50
MPC		0.098
ClinPred		0.37	T
GERP RS		5.1
Varity_R		0.22
gMVP		0.49

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: rs1246323077; hg19: chr9-98209274;