NM_000264.5:c.1262C>T

Variant names:

• chr9-95478140-G-A
• rs1285775586
• NM_000264.5:c.1262C>T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000264.5(PTCH1):​c.1262C>T​(p.Ser421Phe) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,890 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. S421C) has been classified as Likely benign.

• 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: 9.60

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PTCH1	NM_000264.5	c.1262C>T	p.Ser421Phe	missense_variant	Exon 9 of 24	ENST00000331920.11	NP_000255.2
PTCH1	NM_001083603.3	c.1259C>T	p.Ser420Phe	missense_variant	Exon 9 of 24	ENST00000437951.6	NP_001077072.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PTCH1	ENST00000331920.11	c.1262C>T	p.Ser421Phe	missense_variant	Exon 9 of 24	5	NM_000264.5	ENSP00000332353.6
PTCH1	ENST00000437951.6	c.1259C>T	p.Ser420Phe	missense_variant	Exon 9 of 24	5	NM_001083603.3	ENSP00000389744.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461890 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727248

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

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Jan 24, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.S421F variant (also known as c.1262C>T), located in coding exon 9 of the PTCH1 gene, results from a C to T substitution at nucleotide position 1262. The serine at codon 421 is replaced by phenylalanine, an amino acid with highly dissimilar properties. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this alteration remains unclear. -

Sep 16, 2021

Sema4, Sema4

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: curation

- -

Gorlin syndrome Uncertain:1

May 13, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with phenylalanine, which is neutral and non-polar, at codon 421 of the PTCH1 protein (p.Ser421Phe). 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: 453778). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.78
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.72	D;.;.;.;.;.;.;.
Eigen	Benign	0.14
Eigen_PC	Uncertain	0.34
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;.;D;D;.;.;D;D
M_CAP	Uncertain	0.094	D
MetaRNN	Uncertain	0.66	D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.036	D
MutationAssessor	Benign	1.2	L;.;.;.;.;.;.;.
PrimateAI	Uncertain	0.73	T
PROVEAN	Uncertain	-2.7	D;N;N;N;N;N;D;D
REVEL	Uncertain	0.52
Sift	Uncertain	0.0020	D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.0020	D;D;D;D;D;D;D;.
Polyphen		0.21	B;P;P;B;B;P;B;.
Vest4		0.83
MutPred		0.64		Loss of disorder (P = 0.0162);.;.;.;.;.;.;.;
MVP		0.59
MPC		0.64
ClinPred		0.94	D
GERP RS		5.6
Varity_R		0.78
gMVP		0.75

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: rs1285775586; hg19: chr9-98240422;