Is BCO1 p.Val166Ile (c.496G>A) pathogenic?

BCO1 p.Val166Ile (c.496G>A) is classified Likely benign in BCO1 (ClinVar, Single submitter, 1 submitter; last evaluated 2023-04-19). AlphaMissense: likely benign (0.0683); Ultra-rare (popmax 0.0552%, nfe).

How common is BCO1 p.Val166Ile (c.496G>A) in the general population?

BCO1 p.Val166Ile (c.496G>A) is ultra-rare (popmax 0.0552%, nfe) (gnomAD).

What do computational predictors say about BCO1 p.Val166Ile (c.496G>A)?

AlphaMissense predicts likely benign (score 0.0683) — an in-silico prediction, not a clinical call.

BCO1 p.Val166Ile

c.496G>A · rs139667928 · VCV2534495

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0683 · ACMG-weighted

gnomAD v4.1

Rare

ultra-rare (popmax 0.0552%, nfe)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Computational evidence

Protein change
AlphaMissense	0.0683	likely benign
REVEL	0.251	benign-leaning
SaProt	LLR -6.80	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 0.42	GERP -1.2, phastCons 0.004
Regional constraint	o/e 1.16	unconstrained · MANE · 52 kb · p 2.8e-05 · regional, not allelic
Overall
CADD	1.877	PHRED · no single calibrated threshold — expert panels disagree

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

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0552% European (non-Finnish) · 651/1,179,988 alleles

Filtering AF 0.0516% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0502%

Overall 0.043% 694/1,614,028 alleles · ultra-rare exomes 653/1,461,820 · genomes 41/152,208 · joint denominator

Ancestry group	Frequency	1 in
European (non-Finnish)grpmax	0.0552%	1,813
Ashkenazi Jewishnot grpmax-eligible	0.0338%	2,961
Admixed American	0.0217%	4,616
Remaining individualsnot grpmax-eligible	0.0208%	4,807
African / African-American	0.00801%	12,486
East Asian	0.00223%	44,900

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: BCO1
Protein: p.Val166Ile
Coding: c.496G>A
MANE Select: NM_017429
dbSNP: rs139667928
Type: single nucleotide variant
Location: chr16:81264664 (GRCh38)
Gene constraint: LOEUF 1.17 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 90.03

Full BCO1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Similar variants

BCO1 p.Arg266Trp Uncertain significance ★★ ⚠ same type
BCO1 p.Thr170Met Uncertain significance ★★ ⚠ same type
BCO1 c.1101+48C>T Benign ★★ same type
BCO1 c.1102-81T>C Benign ★★ same type
BCO1 c.1303-13G>A Benign ★★ same type
BCO1 c.1303-70A>G Benign ★★ same type
BCO1 c.194-219A>G Benign ★★ same type
BCO1 c.194-74A>G Benign ★★ 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/bco1-p-val166ile (accessed [today's date]).

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