Is TRNT1 p.Asp77= (c.231T>C) pathogenic?

TRNT1 p.Asp77= (c.231T>C) is classified Benign/Likely benign in TRNT1 (ClinVar, Multiple submitters, 5 submitters; last evaluated 2026-06-01). Low-frequency (popmax 1.05%, afr); Associated with congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome.

How common is TRNT1 p.Asp77= (c.231T>C) in the general population?

TRNT1 p.Asp77= (c.231T>C) is low-frequency (popmax 1.05%, afr) (gnomAD).

TRNT1 p.Asp77=

Q: What condition is associated with TRNT1 p.Asp77= (c.231T>C)?

TRNT1 p.Asp77= (c.231T>C) is associated with congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome (ClinVar).

Q: How is Congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome inherited?

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

c.231T>C · rs114362638 · VCV381865

Benign/Likely benign Multiple submitters

Classification

Benign/Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 5 submitters

gnomAD v4.1

Rare

low-frequency (popmax 1.05%, afr)

Conditions

congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome

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 -0.42	GERP -4.6, phastCons 0.21
Overall
CADD	4.886	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 1.05% African / African-American · 788/75,032 alleles

Filtering AF 0.989% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.965%

Overall 0.055% 887/1,613,938 alleles · low-frequency exomes 431/1,461,668 · genomes 456/152,270 · joint denominator

Ancestry group	Frequency	1 in
African / African-Americangrpmax	1.05%	95
Remaining individualsnot grpmax-eligible	0.0784%	1,275
Admixed American	0.065%	1,539
Middle Eastern	0.033%	3,031
South Asian	0.0022%	45,537
European (non-Finnish)	0.000593%	168,553

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: TRNT1
Protein: p.Asp77=
Coding: c.231T>C
MANE Select: NM_182916
dbSNP: rs114362638
Type: single nucleotide variant
Location: chr3:3137342 (GRCh38)
Gene constraint: LOEUF 1.232 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 90.00 · 3 PDB
Residue 77: a binding site

Full TRNT1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

TRNT1 p.Arg190Ile Pathogenic ★★ same condition
TRNT1 p.Arg412Ter Pathogenic/Likely pathogenic ★★ same condition
TRNT1 p.Glu277Ter Pathogenic/Likely pathogenic ★★ same condition
TRNT1 p.Ile223Thr Pathogenic ★★ same condition
TRNT1 p.Lys416Glu Pathogenic/Likely pathogenic ★★ ⚠ same condition
TRNT1 p.Ala273Gly Uncertain significance ★★ ⚠ same condition
TRNT1 p.Ala316Thr Uncertain significance ★★ ⚠ same condition
TRNT1 p.Ala358Gly 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/trnt1-p-asp77 (accessed [today's date]).

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