Is PTCH2 p.Pro678= (c.2034G>A) pathogenic?

PTCH2 p.Pro678= (c.2034G>A) is classified Likely benign in PTCH2 (ClinVar, Single submitter, 1 submitter; last evaluated 2023-12-21). Very rare (popmax 0.00549%, sas); Associated with nevoid basal cell carcinoma syndrome.

What condition is associated with PTCH2 p.Pro678= (c.2034G>A)?

PTCH2 p.Pro678= (c.2034G>A) is associated with nevoid basal cell carcinoma syndrome (ClinVar).

How common is PTCH2 p.Pro678= (c.2034G>A) in the general population?

PTCH2 p.Pro678= (c.2034G>A) is very rare (popmax 0.00549%, sas) (gnomAD).

PTCH2 p.Pro678=

c.2034G>A · rs767584655 · VCV1132091

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00549%, sas)

Conditions

nevoid basal cell carcinoma syndrome

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -0.031	GERP -2.4, phastCons 0.022
Overall
CADD	7.314	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00549% South Asian · 5/91,092 alleles

Filtering AF 0.00223% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00198%

Overall 0.00273% 44/1,614,028 alleles · very rare exomes 43/1,461,786 · genomes 1/152,242 · joint denominator

Ancestry group	Frequency	1 in
South Asiangrpmax	0.00549%	18,218
East Asian	0.00445%	22,450
European (non-Finnish)	0.00305%	32,779
Remaining individualsnot grpmax-eligible	0.0016%	62,488

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: PTCH2
Protein: p.Pro678=
Coding: c.2034G>A
MANE Select: NM_003738
dbSNP: rs767584655
Type: single nucleotide variant
Location: chr1:44827867 (GRCh38)
Gene constraint: LOEUF 0.895 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 79.25
Residue 678: the 'pre-tm7' region

Full PTCH2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

nevoid basal cell carcinoma syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

PTCH2 p.Pro678Leu Uncertain significance ★ ⚠ same residue
PTCH2 c.2976+2T>C Uncertain significance ★★ same condition
PTCH2 c.526-2A>G Uncertain significance ★★ same condition
PTCH2 c.618-6C>A Uncertain significance ★★ same condition
PTCH2 p.Ala1052Thr Uncertain significance ★★ ⚠ same condition
PTCH2 p.Ala1090Val Uncertain significance ★★ ⚠ same condition
PTCH2 p.Ala203Val Uncertain significance ★★ same condition
PTCH2 p.Ala21Thr Uncertain significance ★★ ⚠ same condition

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/ptch2-p-pro678 (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown