Methylenetetrahydrofolate Reductase Mutation Detection (Thermolabile Form) (C677T & A1298C)
Order Code: MTHFR
Epic Lab Code: LAB3642
Order Form: A-1a Miscellaneous Request or Epic Req
Commercial Mail-out Laboratory
6240 RCP
356-3527
Specimen:
Whole Blood
Collection Medium:
Pink top tube
Alternate Collection Media:
Yellow top tube (ACD solution A), Light Blue top tube 2.7 mL (Na Citrate), Light Green top tube (Lithium Heparin), Green top tube 4 mL (Na Heparin)
Minimum:
Adult preferred minimum: One 6 mL pink top tube Adult absolute minimum: 5 mL Pediatric minimum: 1 mL
Rejection Criteria:
Serum, plasma, frozen whole blood, clotted blood, and severely hemolyzed specimens.
Analytic Time:
1 week upon receipt at reference laboratory
Reference Range:
Negative: Neither of the common MTHFR gene mutations tested, C677T and A1298C, were detected. Other causes of elevated homocysteine levels, coronary heart disease, or thrombosis cannot be excluded. This genotype is associated with a normal folate metabolism.
Interpretive Data:
Background Information for Methylenetetrahydrofolate Reductase (MTHFR) 2 Mutations: Characteristics: Mutations in the MTHFR gene (C677T and A1298C) correlate with reduced enzyme activity; however, only homozygotes for C677T or compound heterozygotes for C677T/A1298C have significantly elevated plasma homocysteine levels and increased risk for premature cardiovascular disease. These individuals may also show toxicity from medications (ie, methotrexate) that affect folate metabolism. Incidence: US allele frequency of C677T = 0.39 and A1298C = 0.17; homozygosity for C677T is 1-15 percent. Inheritance: Autosomal recessive. Cause: Homozygosity for MTHFR gene mutation C677T or compound heterozygosity for C677T/A1298C. Mutations Tested: c.677C>T and c.1298A>C. Clinical Sensitivity: Undefined. Sensitivity is dependent upon multiple contributing factors. Analytical Sensitivity & Specificity: 99 percent
Comments:
Please print, complete and submit the following form to the lab, with the specimen and the A-1a Miscellaneous Request: Patient History For Molecular Genetic Testing from ARUP Laboratories.
Test Limitations:
Only the two MTHFR gene mutations (C677T and A1298C) will be targeted; rare diagnostic errors may occur due to primer site mutations.
Methodology:
Polymerase Chain Reaction/Fluorescence Monitoring
CPT Code:
83891, 83900, 83896(x4); additional CPT code modifiers may be required for procedures performed to test for oncologic or inherited disorders.