rs1131690974

Positions:

• chr9-95477671-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000264.5(PTCH1):​c.1379G>A​(p.Trp460Ter) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PTCH1 NM_000264.5 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.39

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 Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 9-95477671-C-T is Pathogenic according to our data. Variant chr9-95477671-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 428824.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-95477671-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PTCH1	NM_000264.5	c.1379G>A	p.Trp460Ter	stop_gained	10/24	ENST00000331920.11	NP_000255.2
PTCH1	NM_001083603.3	c.1376G>A	p.Trp459Ter	stop_gained	10/24	ENST00000437951.6	NP_001077072.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PTCH1	ENST00000331920.11	c.1379G>A	p.Trp460Ter	stop_gained	10/24	5	NM_000264.5	ENSP00000332353	A2
PTCH1	ENST00000437951.6	c.1376G>A	p.Trp459Ter	stop_gained	10/24	5	NM_001083603.3	ENSP00000389744

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461880 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727242

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.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Gorlin syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 29, 2019

For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in PTCH1 are known to be pathogenic (PMID: 16301862, 16419085). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. This variant has been observed in individuals affected with basal cell nevus syndrome (PMID: 8981943, 29575684). This variant is also known as G1368A in the literature. ClinVar contains an entry for this variant (Variation ID: 428824). This variant is not present in population databases (ExAC no frequency). This sequence change creates a premature translational stop signal (p.Trp460*) in the PTCH1 gene. It is expected to result in an absent or disrupted protein product. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 06, 2014

The p.W460* pathogenic mutation (also known as c.1379G>A) located in coding exon 10 of the PTCH1 gene, results from a G to A substitution at nucleotide position 1379. This changes the amino acid from a tryptophan to a stop codon within coding exon 10. This pathogenic mutation has been reported in a sporadic case of nevoid basal cell-carcinoma syndrome (Wicking C et al. Am J Hum Genet. 1997 Jan;60(1):21-6). In addition to the clinical data presented in the literature, since premature stop codons are typically deleterious in nature, this alteration is interpreted as a disease-causing mutation (ACMG Recommendations for Standards for Interpretation and Reporting of Sequence Variations. Revision 2007. Genet Med. 2008;10:294). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	39
DANN	Uncertain	1.0
Eigen	Pathogenic	0.95
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.98	D
MutationTaster	Benign	1.0	A;A;A;A;A;A;A
Vest4		0.98
GERP RS		5.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1131690974; hg19: chr9-98239953;