Is CCDC78 p.Val66= (c.198C>T) pathogenic?

CCDC78 p.Val66= (c.198C>T) is classified Likely benign in CCDC78 (ClinVar, Single submitter, 1 submitter; last evaluated 2023-10-18). Very rare (popmax 0.0067%, amr); Associated with congenital myopathy with internal nuclei and atypical cores.

What condition is associated with CCDC78 p.Val66= (c.198C>T)?

CCDC78 p.Val66= (c.198C>T) is associated with congenital myopathy with internal nuclei and atypical cores (ClinVar).

How common is CCDC78 p.Val66= (c.198C>T) in the general population?

CCDC78 p.Val66= (c.198C>T) is very rare (popmax 0.0067%, amr) (gnomAD).

CCDC78 p.Val66=

Q: How is Congenital myopathy with internal nuclei and atypical cores inherited?

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

c.198C>T · rs753929100 · VCV1595714

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.0067%, amr)

Conditions

congenital myopathy with internal nuclei and atypical cores

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 -4.7	GERP -4
Overall
CADD	1.03	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0067% Admixed American · 4/59,714 alleles

Filtering AF 0.00226% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00135%

Overall 0.000621% 10/1,610,830 alleles · very rare exomes 8/1,458,614 · genomes 2/152,216 · joint denominator

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.0067%	14,928
African / African-American	0.00401%	24,961
Finnishnot grpmax-eligible	0.00315%	31,732
European (non-Finnish)	8.48e-05%	1,178,714

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: CCDC78
Protein: p.Val66=
Coding: c.198C>T
MANE Select: NM_001378030
dbSNP: rs753929100
Type: single nucleotide variant
Location: chr16:725863 (GRCh38)
Gene constraint: LOEUF 1.615 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 66.65

Full CCDC78 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

congenital myopathy with internal nuclei and atypical cores — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Congenital myopathy with internal nuclei and atypical cores (Orphanet):

Inheritance: Autosomal dominant
Onset: Neonatal

Similar variants

CCDC78 p.Val66Gly Uncertain significance ★★ same residue
CCDC78 p.Val66Ile Conflicting classifications of pathogenicity ★ ⚠ same residue
CCDC78 p.Val66fs Uncertain significance ★ same residue
CCDC78 c.1053+1G>A Uncertain significance ★★ same condition
CCDC78 c.268-3C>T Uncertain significance ★★ same condition
CCDC78 c.61-1G>A Uncertain significance ★★ same condition
CCDC78 c.61-6C>A Uncertain significance ★★ same condition
CCDC78 c.953+1G>A 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/ccdc78-p-val66 (accessed [today's date]).

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