Is PRKDC p.Ala266= (c.798T>C) pathogenic?

PRKDC p.Ala266= (c.798T>C) is classified Likely benign in PRKDC (ClinVar, Multiple submitters, 2 submitters; last evaluated 2024-11-05). Very rare (popmax 0.00129%, nfe); Associated with severe combined immunodeficiency due to DNA-PKcs deficiency.

What condition is associated with PRKDC p.Ala266= (c.798T>C)?

PRKDC p.Ala266= (c.798T>C) is associated with severe combined immunodeficiency due to DNA-PKcs deficiency (ClinVar).

How common is PRKDC p.Ala266= (c.798T>C) in the general population?

PRKDC p.Ala266= (c.798T>C) is very rare (popmax 0.00129%, nfe) (gnomAD).

PRKDC p.Ala266=

Q: How is Severe combined immunodeficiency due to DNA-PKcs deficiency inherited?

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

c.798T>C · rs2154504158 · VCV1150815

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

very rare (popmax 0.00129%, nfe)

Conditions

severe combined immunodeficiency due to DNA-PKcs 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 -5.4	GERP -4.3
Overall
CADD	1.118	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00129% European (non-Finnish) · 15/1,166,628 alleles

Filtering AF 0.000772% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000612%

Overall 0.000942% 15/1,592,066 alleles · very rare exomes 15/1,439,718 · genomes 0/152,348 · joint denominator

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: PRKDC
Protein: p.Ala266=
Coding: c.798T>C
MANE Select: NM_006904
dbSNP: rs2154504158
Type: single nucleotide variant
Location: chr8:47943863 (GRCh38)
Gene constraint: LOEUF 0.183 · pLI 1.00 (gnomAD)

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

Disease context

severe combined immunodeficiency due to DNA-PKcs deficiency — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Severe combined immunodeficiency due to DNA-PKcs deficiency (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

PRKDC p.Ala266Val Uncertain significance ★ ⚠ same residue
PRKDC c.2259+6C>T Uncertain significance ★★ same condition
PRKDC c.3464+4G>A Uncertain significance ★★ same condition
PRKDC c.5235+6T>C Uncertain significance ★★ same condition
PRKDC c.5919+5G>A Uncertain significance ★★ same condition
PRKDC p.Ala1008Val Uncertain significance ★★ ⚠ same condition
PRKDC p.Ala1103Val Uncertain significance ★★ ⚠ same condition
PRKDC p.Ala1130Ser 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/prkdc-p-ala266 (accessed [today's date]).

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