Is PDE6B p.Arg20Cys (c.58C>T) pathogenic?

PDE6B p.Arg20Cys (c.58C>T) is classified Uncertain significance in PDE6B (ClinVar, Single submitter, 1 submitter; last evaluated 2025-05-04). AlphaMissense: likely benign (0.0867); Very rare (popmax 0.00668%, eas).

How common is PDE6B p.Arg20Cys (c.58C>T) in the general population?

PDE6B p.Arg20Cys (c.58C>T) is very rare (popmax 0.00668%, eas) (gnomAD).

What do computational predictors say about PDE6B p.Arg20Cys (c.58C>T)?

AlphaMissense predicts likely benign (score 0.0867) — an in-silico prediction, not a clinical call.

PDE6B p.Arg20Cys

c.58C>T · rs558368752 · VCV956267

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0867 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00668%, eas)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Computational evidence

Protein change
AlphaMissense	0.0867	likely benign
REVEL	0.147	moderately benign-leaning
SaProt	LLR -8.79	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 2.5	GERP -3.2, phastCons 0.048
Regional constraint	o/e 1.03	unconstrained · MANE · 44 kb · p 0.27 · regional, not allelic
Overall
CADD	20.5	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — a triage signal, not a reclassification

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00668% East Asian · 3/44,880 alleles

Filtering AF 0.00177% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00134%

Overall 0.00235% 38/1,613,970 alleles · very rare

Ancestry group	Frequency	1 in
East Asiangrpmax	0.00668%	14,960
South Asian	0.00439%	22,771
Ashkenazi Jewishnot grpmax-eligible	0.00338%	29,606
European (non-Finnish)	0.00229%	43,703
Admixed American	0.00167%	60,026
Remaining individualsnot grpmax-eligible	0.0016%	62,508
African / African-American	0.00133%	75,056

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: PDE6B
Protein: p.Arg20Cys
Coding: c.58C>T
MANE Select: NM_000283
dbSNP: rs558368752
Type: single nucleotide variant
Location: chr4:625684 (GRCh38)
Gene constraint: LOEUF 1.238 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 89.72

Full PDE6B gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Similar variants

PDE6B p.Arg20His Conflicting classifications of pathogenicity ★ ⚠ same residue
PDE6B c.1059+2T>G Likely pathogenic ★★ same type
PDE6B c.1060-1G>T Pathogenic/Likely pathogenic ★★ same type
PDE6B c.1107+1G>T Likely pathogenic ★★ same type
PDE6B c.1107+3A>G Pathogenic/Likely pathogenic ★★ same type
PDE6B c.1468-2A>G Pathogenic/Likely pathogenic ★★ same type
PDE6B c.1832+1G>T Pathogenic ★★ same type
PDE6B c.1921-1G>A Pathogenic ★★ same type

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/pde6b-p-arg20cys (accessed [today's date]).

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