rs774219740

Positions:

• chr1-44841883-T-C

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_Strong BS2

The NM_003738.5(PTCH2):​c.229A>G​(p.Ile77Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000233 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. I77I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000023 (0 hom.)
• Consequence: PTCH2 NM_003738.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.754

Genes affected

PTCH2 (HGNC:9586): (patched 2) This gene encodes a transmembrane receptor of the patched gene family. The encoded protein may function as a tumor suppressor in the hedgehog signaling pathway. Alterations in this gene have been associated with nevoid basal cell carcinoma syndrome, basal cell carcinoma, medulloblastoma, and susceptibility to congenital macrostomia. Alternatively spliced transcript variants have been described.[provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Benign. Variant got -8 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.043468237).
• BS2: High AC in GnomAdExome4 at 34 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PTCH2	NM_003738.5	c.229A>G	p.Ile77Val	missense_variant	2/22	ENST00000372192.4	NP_003729.3
PTCH2	NM_001166292.2	c.229A>G	p.Ile77Val	missense_variant	2/23		NP_001159764.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PTCH2	ENST00000372192.4	c.229A>G	p.Ile77Val	missense_variant	2/22	1	NM_003738.5	ENSP00000361266.3
PTCH2	ENST00000447098.6	c.229A>G	p.Ile77Val	missense_variant	2/23	1		ENSP00000389703.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251482 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135920

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: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000233 AC: 34 AN: 1461888 Hom.: 0 Cov.: 33 AF XY: 0.0000193 AC XY: 14 AN XY: 727244

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: 0.0000187

Gnomad4 NFE exome AF: 0.0000279

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 16, 2022

The c.229A>G (p.I77V) alteration is located in exon 2 (coding exon 2) of the PTCH2 gene. This alteration results from a A to G substitution at nucleotide position 229, causing the isoleucine (I) at amino acid position 77 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Gorlin syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 10, 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 PTCH2 protein function. ClinVar contains an entry for this variant (Variation ID: 453932). This variant has not been reported in the literature in individuals affected with PTCH2-related conditions. This variant is present in population databases (rs774219740, gnomAD 0.002%). This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 77 of the PTCH2 protein (p.Ile77Val). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.060
BayesDel_addAF	Benign	-0.19	T
BayesDel_noAF	Benign	-0.50
CADD	Benign	0.41
DANN	Benign	0.61
DEOGEN2	Benign	0.076	.;T
Eigen	Benign	-1.6
Eigen_PC	Benign	-1.6
FATHMM_MKL	Benign	0.028	N
LIST_S2	Benign	0.75	T;T
M_CAP	Benign	0.037	D
MetaRNN	Benign	0.043	T;T
MetaSVM	Benign	-0.58	T
MutationAssessor	Benign	-0.12	N;N
PrimateAI	Benign	0.27	T
PROVEAN	Benign	0.52	N;N
REVEL	Benign	0.17
Sift	Benign	0.33	T;T
Sift4G	Benign	0.32	T;T
Polyphen		0.0	.;B
Vest4		0.079
MutPred		0.47		Loss of catalytic residue at L82 (P = 0.074);Loss of catalytic residue at L82 (P = 0.074);
MVP		0.79
MPC		0.14
ClinPred		0.083	T
GERP RS		-4.3
Varity_R		0.026
gMVP		0.25

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: rs774219740; hg19: chr1-45307555;