MECP2 Genetic Testing Coding and Billing Guidelines (CM00052, V2)
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October 17, 2017

MECP2 Genetic Testing Coding and Billing Guidelines (CM00052, V2)

Effective for dates of service on and after February 19, 2013.

Mutations found in methyl CpG binding protein 2(MECP2) are associated with Rett syndrome. In classic Rett syndrome, suspected cases are identified through specific clinical criteria in female children ages 1-5. Genetic testing is used to confirm the clinical findings. Since 99% of classic cases result in a single random mutation, genetic testing is not useful to screen carriers. Therefore, MolDX has determined that MECP2 genetic testing is not a Medicare benefit and is a statutorily excluded service. In addition to single disease testing, MolDX will also deny panels of tests that include a MECP2 gene test as a statutorily excluded service.

To receive a MECP2 test denial, please submit the following claim information:

  • Appropriate CPT code for test (CPT codes 81302-81304)
    • CPT code 81302- MECP2, full gene sequence
    • CPT code 81303- MECP2, known familial variant
    • CPT code 81304- MECP2, duplication/deletion variants
    • CPT code 81479- MECP2, panel
  • An Advance Beneficiary Notice of Non-Coverage (ABN)External Website is not required for statutorily excluded services.
    • For a voluntary issued ABN, append with HCPCS modifier GX
    • To indicate a valid ABN is on file for a known statutorily excluded service, append with HCPCS modifier GY
  • Select the appropriate diagnosis for the patient
  • Enter the appropriate DEX Z-code™ identifier adjacent to the CPT code in the comment/narrative field for the following claim field/types:
    • Part A: Line SV202-7 (electronic claim); Block 80 (paper claim)
    • Part B: Loop 2400 or SV101-7 (electronic claim); Item 19 (paper claim)

Reference: Sec. 1862 (1)(A) Statutory Exclusion covers diagnostic testing “except for items and services that are not reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member,…”

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