Uracil

ChemistryAlso known as: 2,4-DihydroxypyrimidineAlso known as: Uracil basemmol/mol creatinine

Measures uracil levels in blood as a marker of pyrimidine metabolism.

Normal Range
0 – 9
mmol/mol creatinine
Abnormal Levels
< 0 mmol/mol creatinine
> 9 mmol/mol creatinine
Specimen Type
Blood

Why This Biomarker Matters

Elevated uracil is rare but can indicate uracil-5-carboxylase deficiency, a genetic metabolic disorder. Early detection through newborn screening allows for dietary management and medical intervention to prevent neurological complications.

Optimal Ranges

Clinician-defined 4-point reference thresholds (mmol/mol creatinine)

Default Range

0
0
9
9
Low
0 mmol/mol creatinine
Borderline Low
0 mmol/mol creatinine
Optimal
9 mmol/mol creatinine
Borderline High
9 mmol/mol creatinine

Overview

Uracil is a nucleobase (building block of RNA) that circulates at low levels in the bloodstream. Elevated uracil levels can indicate uracil-5-carboxylase deficiency, a rare metabolic disorder affecting pyrimidine metabolism. Patients with this deficiency may experience delayed development, microcephaly, or other neurological symptoms. Testing uracil levels helps diagnose rare inborn errors of metabolism. Most individuals have undetectable or very low uracil, so any elevation warrants further metabolic investigation.

Technical Information (LOINC Codes)

Standardized laboratory codes for this biomarker

75152-9Primary
Uracil [Moles/volume] in Serum or Plasma
nmol/L
30485-7
Uracil [Presence] in Urine
75128-9
Uracil [Moles/volume] in Cerebral spinal fluid
nmol/L
96043-5
Uracil [Mass/volume] in Serum or Plasma
ng/mL

Available Lab Tests

Order tests that measure this biomarker

Urinary Organic Acids

$586.08
Results in 7-14 business days