Q92.62
BillableMarker chromosomes in abnormal individual
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is Q92.62 an HCC code?
No. Q92.62 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for Q92.62
For Q92.62to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed Q92.62 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
Q92.62 is the ICD-10-CM diagnosis code for marker chromosomes in abnormal individual. Small extra chromosomal fragments (marker chromosomes) found in a person with developmental abnormalities or other clinical manifestations. Q92.62 sits in the ICD-10-CM chapter for congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (q00-qa0), within the section covering chromosomal abnormalities, not elsewhere classified (q90-q99).
Q92.62 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.
This code maps to RxHCC 148 (Mild Intellectual Disabilities) with a RAF weight of 0.0 in the RxHCC model. While it doesn't contribute to risk adjustment scoring, it's important for identifying patients who may require specialized medications for developmental or neurological conditions.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for Q92.62 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code when marker chromosomes are associated with clinical symptoms or abnormalities
- •Document the associated abnormalities for complete clinical documentation
Clinical Significance
Marker chromosomes represent significant chromosomal abnormalities that can cause developmental delays, intellectual disabilities, and multiple congenital anomalies. This diagnosis indicates the presence of small extra chromosomal fragments that may contain important genetic material, requiring ongoing monitoring for associated complications and developmental support services.
Documentation Requirements
- ✓Cytogenetic analysis results showing marker chromosomes
- ✓Clinical manifestations or abnormalities present
- ✓Developmental assessment findings
- ✓Family history of chromosomal abnormalities
- ✓Genetic counseling documentation
- ✓Associated congenital anomalies or syndromes
- ✓Intellectual or developmental disability assessment
- ✓Specialist consultation notes (genetics, neurology)
Commonly Confused Codes
- •Q928 — Other specified trisomies involve extra chromosome material but not marker chromosomes specifically
- •Q929 — Unspecified trisomy lacks the specific identification of marker chromosomes
- •Q9359 — Other chromosomal deletions involve missing rather than extra chromosomal material
- •Q9388 — Other microdeletions are deletions not extra marker chromosomes