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Prior Authorization Required*
*If prior authorization is not submitted, test may be delayed.
Test Overview
Test Methodology

The coding exons and associated, flanking splice sites of the KRAS gene are amplified using specific primers, and bidirectionally sequenced using a fluorescent method.

Test Usage

To detect the presence of KRAS mutations in patients with a diagnosis of Noonan syndrome, Cardio-facio-cutaneous (CFC) syndrome, or Costello syndrome, particularly if PTPN11 and SOS1 testing for Noonan syndrome was previously performed, and for carrier testing in families with a known KRAS mutation. All coding exons and associated flanking splice sites of the KRAS gene will be sequenced.

Reference Range *

Interpretive report provided.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

This assay will not detect large deletions in the KRAS gene or intronic mutations outside region sequenced in the KRAS gene. In addition, mutations in other genes associated with the aforementioned syndromes will not be detected. This test is not suitable for the detection of mutations in codons 12, 13, and 61 of the KRAS gene using DNA extracted from formalin-fixed paraffin-embedded tissue blocks.

Test Details
Days Set Up
Monday - Friday
Analytic Time

21 - 28 days

Soft Order Code
MiChart Code
KRAS Gene Sequencing in Inherited Disorders
  • KRAS test in inherited disease
  • KRAS-inherited disease,shadow
  • Noonan Syndrome
  • Cardio Facio Cutaneous (CFC) Syndrome
  • Costello Syndrome
  • v-Ki-Ras2 Kirsten Rat Sarcoma viral oncogene homolog Gene Sequencing
  • KRAS / KRAS2 Mutation Analysis
  • RASK / RASK2 Mutation Analysis
MMGL Molecular Genetics
Specimen Requirements
Collection Instructions

Collect specimen in a lavender top tube. Send intact specimen within 24 hours if stored at room temperature or within 5 days if stored refrigerated. Include the patient's family history, pedigree, and ethnicity on the test requisition. Obtaining informed consent from the patient prior to genetic testing is strongly recommended. If desired, a UMHS Request and Consent for Genetic Testing form can be obtained from the MMGL Molecular Genetics Laboratory by contacting the MLabs Client Services Center at 800-862-7284 or online at

Normal Volume
5 - 10 mL EDTA whole blood
Minimum Volume
2 mL EDTA whole blood
Additional Information

By ordering this test the clinician acknowledges that informed consent has been obtained from the patient as required by applicable state or federal laws and the ordering clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. Test includes medical geneticist interpretation of results billed as a separate additional charge. This test is not available without interpretation.

CPT Code
Fee Code
Pro Fee CPT