Is BTD p.Glu74Ter (c.220G>T) pathogenic?

BTD p.Glu74Ter (c.220G>T) is classified Likely pathogenic in BTD (ClinVar, Single submitter, 1 submitter; last evaluated 2021-12-30). Very rare (popmax 8.47e-05%, nfe); Associated with biotinidase deficiency.

What condition is associated with BTD p.Glu74Ter (c.220G>T)?

BTD p.Glu74Ter (c.220G>T) is associated with biotinidase deficiency (ClinVar).

How common is BTD p.Glu74Ter (c.220G>T) in the general population?

BTD p.Glu74Ter (c.220G>T) is very rare (popmax 8.47e-05%, nfe) (gnomAD).

How is Biotinidase deficiency inherited?

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

BTD p.Glu74Ter

c.220G>T · rs2065328619 · VCV1726713

Likely pathogenic Single submitter

Classification

Likely pathogenic

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 8.47e-05%, nfe)

Conditions

biotinidase deficiency

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation/SpliceAI carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function
NMD	predicted	premature termination codon in exon 2 of 4
Splicing
SpliceAI	Δ0.20	donor loss · deltas
Pangolin	Δ0.20	loss · gain 0.01 · agrees with SpliceAI · independent
Constraint at this position
Conservation	phyloP 9.8	GERP 1.4, phastCons 1
Overall
CADD	44.0	PHRED · no single calibrated threshold — expert panels disagree

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 8.47e-05% European (non-Finnish) · 1/1,180,038 alleles

Overall 6.84e-05% 1/1,461,884 alleles · very rare

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: BTD
Protein: p.Glu74Ter
Coding: c.220G>T
MANE Select: NM_001370658
dbSNP: rs2065328619
Type: single nucleotide variant
Location: chr3:15635659 (GRCh38)
Gene constraint: LOEUF 1.22 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 86.77
Residue 74: the cn hydrolase domain

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

Disease context

biotinidase deficiency — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Biotinidase deficiency (Orphanet):

Inheritance: Autosomal recessive
Onset: Adolescent, Adult, Childhood, Infancy, Neonatal
Prevalence: 1-9 / 100 000 (Worldwide)

Similar variants

BTD c.1330G>C Pathogenic ★★ same condition
BTD c.249+1G>T Likely pathogenic ★★ same condition
BTD c.400-2A>G Likely pathogenic ★★ same condition
BTD c.-17+2T>C Pathogenic/Likely pathogenic ★★ same condition
BTD p.Ala142Val Pathogenic/Likely pathogenic ★★ same condition
BTD p.Ala217Thr Pathogenic/Likely pathogenic ★★ ⚠ same condition
BTD p.Ala269Val Pathogenic/Likely pathogenic ★★ same condition
BTD p.Ala279Pro Pathogenic/Likely pathogenic ★★ 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/btd-p-glu74ter (accessed [today's date]).

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