Is MOCOS p.Phe68= (c.204C>T) pathogenic?

MOCOS p.Phe68= (c.204C>T) is classified Likely benign in MOCOS (ClinVar, Single submitter, 1 submitter; last evaluated 2023-06-24). Very rare (popmax 0.00186%, nfe); Associated with xanthinuria type II.

What condition is associated with MOCOS p.Phe68= (c.204C>T)?

MOCOS p.Phe68= (c.204C>T) is associated with xanthinuria type II (ClinVar).

How common is MOCOS p.Phe68= (c.204C>T) in the general population?

MOCOS p.Phe68= (c.204C>T) is very rare (popmax 0.00186%, nfe) (gnomAD).

How is Hereditary xanthinuria inherited?

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

MOCOS p.Phe68=

c.204C>T · rs200262581 · VCV2975216

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00186%, nfe)

Conditions

xanthinuria type II

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	<0.2	all four deltas below 0.2 · C>A here scores Δ0.27 · evaluated, not missing
Constraint at this position
Conservation	phyloP 2.6	GERP -0.049, phastCons 1
Overall
CADD	11.98	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00186% European (non-Finnish) · 22/1,179,986 alleles

Filtering AF 0.00122% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00104%

Overall 0.00136% 22/1,614,138 alleles · very rare exomes 22/1,461,824 · genomes 0/152,314 · 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: MOCOS
Protein: p.Phe68=
Coding: c.204C>T
MANE Select: NM_017947
dbSNP: rs200262581
Type: single nucleotide variant
Location: chr18:36195318 (GRCh38)
Gene constraint: LOEUF 1.19 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 80.88

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

Disease context

xanthinuria type II — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Hereditary xanthinuria (Orphanet):

Inheritance: Autosomal recessive
Onset: All ages

Similar variants

MOCOS c.1218+1G>C Likely pathogenic ★★ same condition
MOCOS c.2164+2T>C Likely pathogenic ★★ same condition
MOCOS c.232+1G>A Likely pathogenic ★★ same condition
MOCOS p.Arg419Ter Pathogenic ★★ same condition
MOCOS p.Arg776Cys Pathogenic/Likely pathogenic ★★ same condition
MOCOS p.Gln516Ter Likely pathogenic ★★ same condition
MOCOS p.Glu42Ter Likely pathogenic ★★ same condition
MOCOS p.Glu763Ter 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/mocos-p-phe68 (accessed [today's date]).

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