9-95467344-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1PM2PM5PP3

The NM_000264.5(PTCH1):​c.2332A>G​(p.Thr778Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,886 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T778P) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

PTCH1
NM_000264.5 missense

Scores

6
9
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 7.67
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM1
In a topological_domain Extracellular (size 257) in uniprot entity PTC1_HUMAN there are 24 pathogenic changes around while only 5 benign (83%) in NM_000264.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr9-95467344-T-G is described in Lovd as [Likely_pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.805

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PTCH1NM_000264.5 linkc.2332A>G p.Thr778Ala missense_variant Exon 15 of 24 ENST00000331920.11 NP_000255.2 Q13635-1
PTCH1NM_001083603.3 linkc.2329A>G p.Thr777Ala missense_variant Exon 15 of 24 ENST00000437951.6 NP_001077072.1 Q13635-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PTCH1ENST00000331920.11 linkc.2332A>G p.Thr778Ala missense_variant Exon 15 of 24 5 NM_000264.5 ENSP00000332353.6 Q13635-1
PTCH1ENST00000437951.6 linkc.2329A>G p.Thr777Ala missense_variant Exon 15 of 24 5 NM_001083603.3 ENSP00000389744.2 Q13635-2

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461886
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
727244
show subpopulations
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: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Gorlin syndrome Uncertain:1
Apr 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 778 of the PTCH1 protein (p.Thr778Ala). 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: 1383715). 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. -

Hereditary cancer-predisposing syndrome Uncertain:1
Nov 11, 2020
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.T778A variant (also known as c.2332A>G), located in coding exon 15 of the PTCH1 gene, results from an A to G substitution at nucleotide position 2332. The threonine at codon 778 is replaced by alanine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. 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
0.33
BayesDel_addAF
Pathogenic
0.28
D
BayesDel_noAF
Pathogenic
0.16
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.78
D;.;.;.;.;.;.
Eigen
Uncertain
0.46
Eigen_PC
Uncertain
0.52
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.79
T;.;T;T;.;.;T
M_CAP
Uncertain
0.12
D
MetaRNN
Pathogenic
0.80
D;D;D;D;D;D;D
MetaSVM
Uncertain
0.32
D
MutationAssessor
Uncertain
2.3
M;.;.;.;.;.;.
PrimateAI
Pathogenic
0.92
D
PROVEAN
Uncertain
-3.8
D;D;D;D;D;D;D
REVEL
Pathogenic
0.78
Sift
Benign
0.042
D;D;D;D;D;D;T
Sift4G
Uncertain
0.0050
D;D;D;D;D;D;D
Polyphen
0.88
P;.;.;P;P;.;P
Vest4
0.77
MutPred
0.58
Loss of stability (P = 0.0895);.;.;.;.;.;.;
MVP
0.80
MPC
1.0
ClinPred
0.98
D
GERP RS
5.7
Varity_R
0.58
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

No publications associated with this variant yet.

Other links and lift over

hg19: chr9-98229626; API