Is TONSL p.Arg873Cys (c.2617C>T) pathogenic?

TONSL p.Arg873Cys (c.2617C>T) is classified Uncertain significance in TONSL (ClinVar, Multiple submitters, 2 submitters; last evaluated 2023-12-20). AlphaMissense: likely benign (0.1322); Very rare (popmax 0.00768%, sas); Associated with Inborn genetic diseases.

What condition is associated with TONSL p.Arg873Cys (c.2617C>T)?

TONSL p.Arg873Cys (c.2617C>T) is associated with Inborn genetic diseases (ClinVar).

How common is TONSL p.Arg873Cys (c.2617C>T) in the general population?

TONSL p.Arg873Cys (c.2617C>T) is very rare (popmax 0.00768%, sas) (gnomAD).

What do computational predictors say about TONSL p.Arg873Cys (c.2617C>T)?

AlphaMissense predicts likely benign (score 0.1322) — an in-silico prediction, not a clinical call.

TONSL p.Arg873Cys

c.2617C>T · rs757192033 · VCV1425861

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

AlphaMissense

likely benign

0.1322 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00768%, sas)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

Inborn genetic diseases

Computational evidence

Protein change
AlphaMissense	0.1322	likely benign
REVEL	0.119	moderately benign-leaning
SaProt	LLR -9.36	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 1.3	GERP -3, phastCons 0.004
Regional constraint	o/e 1.01	unconstrained · MANE · 15 kb · p 0.67 · regional, not allelic
Overall
CADD	19.85	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 0.00768% South Asian · 7/91,088 alleles

Filtering AF 0.00359% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00255%

Overall 0.00124% 20/1,612,546 alleles · very rare exomes 17/1,460,530 · genomes 3/152,016 · joint denominator

Ancestry group	Frequency	1 in
South Asiangrpmax	0.00768%	13,013
Admixed American	0.005%	19,999
East Asian	0.00446%	22,421
Remaining individualsnot grpmax-eligible	0.0016%	62,462
African / African-American	0.00134%	74,866
European (non-Finnish)	0.000509%	196,637

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: TONSL
Protein: p.Arg873Cys
Coding: c.2617C>T
MANE Select: NM_013432
dbSNP: rs757192033
Type: single nucleotide variant
Location: chr8:144435816 (GRCh38)
Gene constraint: LOEUF 1.024 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 76.06 · 3 PDB
Residue 873: the 'disordered' region; a UniProt-annotated variant site (in semdsp; disease phenotype includes immunologic and hematologic abnormalities); a UniProt-annotated variant site (in semdsp); a UniProt-annotated variant site (in semdsp; disease phenotype includes primary aphakia and absent pupils)

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

Disease context

Inborn genetic diseases — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

TONSL p.Arg873Pro Uncertain significance ★★ ⚠ same residue
TONSL p.Arg873His Uncertain significance ★ ⚠ same residue
TONSL p.Ala1053Ser Uncertain significance ★★ ⚠ same condition
TONSL p.Ala1065Ser Uncertain significance ★★ ⚠ same condition
TONSL p.Ala1093Ser Uncertain significance ★★ ⚠ same condition
TONSL p.Ala1200Thr Uncertain significance ★★ ⚠ same condition
TONSL p.Ala215Thr Uncertain significance ★★ ⚠ same condition
TONSL p.Ala232Val 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/tonsl-p-arg873cys (accessed [today's date]).

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