MOCOS

Chr 18AR

molybdenum cofactor sulfurase

Also known as: HMCS, MCS, MOS

The protein sulfurates the molybdenum cofactor, which is essential for the activity of xanthine dehydrogenase and aldehyde oxidase enzymes involved in purine metabolism. Biallelic mutations cause autosomal recessive xanthinuria type II, a metabolic disorder characterized by decreased uric acid levels, elevated xanthine and hypoxanthine in serum and urine, xanthine kidney stones, and myositis from tissue xanthine deposition. The gene shows very low constraint against loss-of-function variants, consistent with the recessive inheritance pattern.

Summary from RefSeq, OMIM, UniProt
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Primary Disease Associations & Inheritance

Xanthinuria, type IIMIM #603592
AR
UniProtXanthinuria 2
0
Active trials
8
Pubs (1 yr)
0
P/LP submissions
P/LP missense
1.15
LOEUF
Mechanism
Clinical SummaryMOCOS
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Gene-Disease Validity (ClinGen)
xanthinuria type II · ARDefinitive

Definitive — sufficient evidence for diagnostic panels

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.15LOEUF
pLI 0.000
Z-score 0.80
OE 0.86 (0.651.15)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.45Z-score
OE missense 1.06 (0.981.14)
503 obs / 475.4 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.86 (0.651.15)
00.351.4
Missense OE1.06 (0.981.14)
00.61.4
Synonymous OE1.02
01.21.6
LoF obs/exp: 32 / 37.2Missense obs/exp: 503 / 475.4Syn Z: -0.17

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

MOCOS · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

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Clinical Literature
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