9-95477547-C-T

Position:

• chr9-95477547-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP5

The NM_000264.5(PTCH1):​c.1503G>A​(p.Gln501Gln) variant causes a splice region, synonymous change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 33)
• Consequence: PTCH1 NM_000264.5 splice_region, synonymous
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• 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]

PTCH1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 9-95477547-C-T is Pathogenic according to our data. Variant chr9-95477547-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 426225.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Likely_pathogenic=1}. Variant chr9-95477547-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.1503G>A	p.Gln501Gln	splice_region_variant, synonymous_variant	10/24	ENST00000331920.11	NP_000255.2
PTCH1	NM_001083603.3	c.1500G>A	p.Gln500Gln	splice_region_variant, synonymous_variant	10/24	ENST00000437951.6	NP_001077072.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PTCH1	ENST00000331920.11	c.1503G>A	p.Gln501Gln	splice_region_variant, synonymous_variant	10/24	5	NM_000264.5	ENSP00000332353.6
PTCH1	ENST00000437951.6	c.1500G>A	p.Gln500Gln	splice_region_variant, synonymous_variant	10/24	5	NM_001083603.3	ENSP00000389744.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Apr 25, 2017

The c.1503G>A variant in the PTCH1 gene has been previously reported in at least one individual pursuing genetic testing for Gorlin syndrome (Klein et al., 2005). Several in silico splice prediction models predict that c.1503G>A destroys the natural splice donor site in intron 10, and is expected to cause abnormal gene splicing. However, in the absence of RNA/functional studies, the actual effect of this sequence change is unknown. Based on currently available evidence, c.1503G>A is a strong candidate for a pathogenic variant. However, the possibility it is a rare benign variant cannot be excluded. -

Gorlin syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 10, 2023

This sequence change affects codon 501 of the PTCH1 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the PTCH1 protein. This variant also falls at the last nucleotide of exon 10, which is part of the consensus splice site for this exon. This variant is not present in population databases (gnomAD no frequency). This variant has been observed in individual(s) with clinical features of nevoid basal cell carcinoma syndrome (PMID: 16301862). ClinVar contains an entry for this variant (Variation ID: 426225). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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
BayesDel_noAF	Benign	-0.19
CADD	Benign	22
DANN	Benign	0.95

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.29		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.29		Position offset: 0

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1085307511; hg19: chr9-98239829;