Is TPP2 p.Pro556= (c.1668G>A) pathogenic?

TPP2 p.Pro556= (c.1668G>A) is classified Likely benign in TPP2 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-03-18). Ultra-rare (popmax 0.0855%, afr); Associated with Evans syndrome, immunodeficiency, and premature immunosenescence associated with tripeptidyl-peptidase II deficiency.

How common is TPP2 p.Pro556= (c.1668G>A) in the general population?

TPP2 p.Pro556= (c.1668G>A) is ultra-rare (popmax 0.0855%, afr) (gnomAD).

TPP2 p.Pro556=

Q: What condition is associated with TPP2 p.Pro556= (c.1668G>A)?

TPP2 p.Pro556= (c.1668G>A) is associated with Evans syndrome, immunodeficiency, and premature immunosenescence associated with tripeptidyl-peptidase II deficiency (ClinVar).

c.1668G>A · rs144307937 · VCV1158442

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

ultra-rare (popmax 0.0855%, afr)

Conditions

Evans syndrome, immunodeficiency, and premature immunosenescence associated with tripeptidyl-peptidase II deficiency

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	<0.2	no splice effect predicted · four deltas, not one · how we know
Constraint at this position
Conservation	phyloP -0.073	GERP -2.6, phastCons 0.013
Overall
CADD	10.64	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0855% African / African-American · 64/74,872 alleles

Filtering AF 0.0687% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0625%

Overall 0.00657% 106/1,612,236 alleles · ultra-rare exomes 69/1,460,212 · genomes 37/152,024 · joint denominator

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.0855%	1,170
East Asian	0.0134%	7,473
Remaining individualsnot grpmax-eligible	0.00481%	20,810
European (non-Finnish)	0.00271%	36,855
Admixed American	0.00168%	59,612

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: TPP2
Protein: p.Pro556=
Coding: c.1668G>A
MANE Select: NM_001330588
dbSNP: rs144307937
Type: single nucleotide variant
Location: chr13:102636382 (GRCh38)
Gene constraint: LOEUF 0.29 · pLI 1.00 (gnomAD)
Structure: AlphaFold pLDDT 91.98

Full TPP2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Evans syndrome, immunodeficiency, and premature immunosenescence associated with tripeptidyl-peptidase II deficiency — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

TPP2 p.Pro556Leu Uncertain significance ★ ⚠ same residue
TPP2 p.Ala619Thr Uncertain significance ★★ ⚠ same condition
TPP2 p.Ala648Asp Uncertain significance ★★ ⚠ same condition
TPP2 p.Arg1072Gln Uncertain significance ★★ ⚠ same condition
TPP2 p.Arg893Cys Uncertain significance ★★ ⚠ same condition
TPP2 p.Asn1192Ser Uncertain significance ★★ ⚠ same condition
TPP2 p.Asn1227Ser Uncertain significance ★★ ⚠ same condition
TPP2 p.Asp86His 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/tpp2-p-pro556 (accessed [today's date]).

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