Is CD8A p.Pro21= (c.63G>A) pathogenic?

CD8A p.Pro21= (c.63G>A) is classified Likely benign in CD8A (ClinVar, Single submitter, 1 submitter; last evaluated 2022-11-10). Very rare (popmax 0.00167%, amr); Associated with susceptibility to respiratory infections associated with CD8alpha chain mutation.

How common is CD8A p.Pro21= (c.63G>A) in the general population?

CD8A p.Pro21= (c.63G>A) is very rare (popmax 0.00167%, amr) (gnomAD).

CD8A p.Pro21=

Q: What condition is associated with CD8A p.Pro21= (c.63G>A)?

CD8A p.Pro21= (c.63G>A) is associated with susceptibility to respiratory infections associated with CD8alpha chain mutation (ClinVar).

Q: How is Susceptibility to respiratory infections associated with CD8alpha chain mutation inherited?

Typically Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

c.63G>A · rs776230766 · VCV2882346

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00167%, amr)

Conditions

susceptibility to respiratory infections associated with CD8alpha chain mutation

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 -4.1	GERP -2.8
Overall
CADD	1.132	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00167% Admixed American · 1/59,884 alleles

Overall 0.000138% 2/1,445,580 alleles · very rare

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.00167%	59,884
European (non-Finnish)	8.48e-05%	1,178,566

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: CD8A
Protein: p.Pro21=
Coding: c.63G>A
MANE Select: NM_001768
dbSNP: rs776230766
Type: single nucleotide variant
Location: chr2:86790668 (GRCh38)
Gene constraint: LOEUF 1.496 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 79.03 · 8 PDB

Full CD8A gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

susceptibility to respiratory infections associated with CD8alpha chain mutation — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Susceptibility to respiratory infections associated with CD8alpha chain mutation (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal
Prevalence: <1 / 1 000 000 (Europe)

Similar variants

CD8A p.Pro21Gln Uncertain significance ★ ⚠ same residue
CD8A c.403+4C>G Uncertain significance ★★ same condition
CD8A c.626-2A>T Uncertain significance ★★ same condition
CD8A p.Arg165Leu Uncertain significance ★★ ⚠ same condition
CD8A p.Arg165Pro Uncertain significance ★★ ⚠ same condition
CD8A p.His127Tyr Uncertain significance ★★ ⚠ same condition
CD8A p.His208Leu Uncertain significance ★★ ⚠ same condition
CD8A p.Leu10Arg 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/cd8a-p-pro21 (accessed [today's date]).

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