Is COG4 p.Asp650= (c.1950C>T) pathogenic?

COG4 p.Asp650= (c.1950C>T) is classified Likely benign in COG4 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-12-29). Very rare (popmax 0.0011%, sas); Associated with COG4-congenital disorder of glycosylation.

What condition is associated with COG4 p.Asp650= (c.1950C>T)?

COG4 p.Asp650= (c.1950C>T) is associated with COG4-congenital disorder of glycosylation (ClinVar).

How common is COG4 p.Asp650= (c.1950C>T) in the general population?

COG4 p.Asp650= (c.1950C>T) is very rare (popmax 0.0011%, sas) (gnomAD).

How is COG4-CDG inherited?

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

COG4 p.Asp650=

c.1950C>T · rs751066238 · VCV2189413

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.0011%, sas)

Conditions

COG4-congenital disorder of glycosylation

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 2.2	GERP 1.6, phastCons 1
Overall
CADD	6.434	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0011% South Asian · 1/91,076 alleles

Filtering AF 0.000359% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00026%

Overall 0.000753% 11/1,461,716 alleles · very rare

Ancestry group	Frequency	1 in
Remaining individualsnot grpmax-eligible	0.0016%	62,490
South Asiangrpmax	0.0011%	91,076
European (non-Finnish)	0.000763%	131,100

Remaining individuals shows a higher raw frequency than the grpmax group above it. gnomAD excludes bottlenecked groups — Finnish, Ashkenazi Jewish, Amish and “Remaining individuals” — from grpmax, because founder effects make their frequencies unrepresentative for filtering. The table is sorted by frequency, so an excluded group can sit above the grpmax row.

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: COG4
Protein: p.Asp650=
Coding: c.1950C>T
MANE Select: NM_015386
dbSNP: rs751066238
Type: single nucleotide variant
Location: chr16:70482146 (GRCh38)
Gene constraint: LOEUF 0.805 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 85.29 · 1 PDB
Residue 650: an α-helix; the 'd domain' region

Full COG4 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

COG4-congenital disorder of glycosylation — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For COG4-CDG (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

COG4 p.Asp650His Uncertain significance ★ same residue
COG4 p.Asp650Asn Uncertain significance ★★ same residue
COG4 p.Arg177Ter Pathogenic/Likely pathogenic ★★ same condition
COG4 p.Arg733Trp Pathogenic/Likely pathogenic ★★ same condition
COG4 p.Glu614Ter Pathogenic ★★ same condition
COG4 p.Gly25Ter Pathogenic/Likely pathogenic ★★ same condition
COG4 p.Gly516Arg Pathogenic ★★ same condition
COG4 p.Ala251Thr 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/cog4-p-asp650 (accessed [today's date]).

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