2025 CPT code 81303
Effective Date: N/A Molecular Pathology Procedures Feed
MECP2 (methyl CpG binding protein 2) (eg, Rett syndrome) gene analysis; known familial variant
Modifier 26 can be used if a physician or other qualified healthcare professional performs the interpretation and report separately from the technical component of the test.
Medical necessity for 81303 is established when there is a documented family history of a known MECP2 mutation and the test is being performed for diagnostic, prenatal, or predictive purposes. The test must be targeted to a specific known familial variant.
The laboratory professional performs the technical aspects of the test, including DNA extraction, amplification, and detection of the specific familial variant. Interpretation of the results is typically performed by a physician or other qualified healthcare professional, and can be reported separately using modifier 26.
In simple words: This test looks for a specific, known genetic change in the MECP2 gene that has already been found in other members of your family.This gene is linked to Rett syndrome.The test helps determine if you or a family member carries the same genetic change.
This code represents the laboratory analysis of the MECP2 gene for known familial variants. It includes all analytical steps involved in testing for specific, pre-identified mutations within this gene that have been previously observed in the patient's family. This test is often used to confirm the presence of a known MECP2 mutation in a family member or for prenatal diagnostic testing when a specific familial mutation is already known.It does not include full gene sequencing or analysis for other variants beyond the known familial variant.The test focuses on detecting the presence or absence of the specific mutation within the MECP2 gene.
Example 1: A pregnant woman has a family history of Rett syndrome and genetic testing has revealed a specific MECP2 mutation in her family. She undergoes prenatal testing using code 81303 to determine if the fetus has inherited the same mutation., A child exhibits developmental delays and symptoms suggestive of Rett syndrome.A known MECP2 mutation has been identified in a family member.The child is tested for the specific familial variant using code 81303., An adult with a family history of Rett syndrome undergoes predictive testing using code 81303 to determine if they carry the familial MECP2 mutation, even if they are asymptomatic.
Documentation should include the patient's family history, the specific known familial variant being tested, the reason for testing (e.g., diagnostic, prenatal, predictive), and the results of the analysis.Prior test reports confirming the familial variant should also be available.
- Specialties:Genetics, Pediatrics, Neurology, Maternal-Fetal Medicine
- Place of Service:Independent Laboratory, Outpatient Hospital, Office