CurrentCapital BluecrossPolicy MP 2.273

Genetic Testing for Mitochondrial Disorders

Customize your policy alerts

Sign up for Capital Bluecross Policy MP 2.273 alerts

Get alerted when Policy MP 2.273 changes without checking for updates manually.

Monitor payer policy activity

Receive email alerts as soon as relevant payer policies are published or updated.

Defines medical necessity, testing strategies, and guidance for genetic testing to establish a diagnosis of mitochondrial disorders and for targeted familial variant testing in at-risk relatives. Applies to providers and members covered under Capital Bluecross products where this policy is in effect.

Policy Summary

PayerCapital Bluecross

PolicyGenetic Testing for Mitochondrial Disorders

Policy CodePolicy MP 2.273

Change TypeMinor / No material clinical changes

Effective DateApr 1, 2026

Last ReviewMar 12, 2026

Next Review DateApr 1, 2026

Key ActionOrder genetic testing when signs/symptoms of a mitochondrial disorder are present and testing may obviate the need for muscle biopsy; document ICD-10 diagnosis and evidence of genetic counseling as applicable.

SourceLink

OpenPayer is powered by Trek Health's payer performance platform. Trek continuously ingests, validates, and normalizes Transparency in Coverage data alongside payer policies and other commercial payer data to create a structured payer intelligence foundation. OpenPayer uses this foundation to deliver personalized search results, dynamically generated policy pages, and tailored policy monitoring based on each user's payers, specialties, billing codes, and areas of interest. The same intelligence powers broader payer performance workflows, including reimbursement benchmarking, contract evaluation, payer negotiations, and financial decision-making.

CurrentCapital BluecrossPolicy MP 2.273

Genetic Testing for Mitochondrial Disorders

Customize your policy alerts

Sign up for Capital Bluecross Policy MP 2.273 alerts

Get alerted when Policy MP 2.273 changes without checking for updates manually.

Monitor payer policy activity

Receive email alerts as soon as relevant payer policies are published or updated.

Policy Summary

PayerCapital Bluecross

PolicyGenetic Testing for Mitochondrial Disorders

Policy CodePolicy MP 2.273

Change TypeMinor / No material clinical changes

Effective DateApr 1, 2026

Last ReviewMar 12, 2026

Next Review DateApr 1, 2026

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

1 in 5000approximate prevalence of mitochondrial disorders

37number of genes in human mitochondrial DNA

15-25%reported diagnostic yield for NGS panels

CLIArequired lab regulatory standard for LDTs

3-generationrecommended family history depth

Coverage Criteria

inv-01: Medically Necessary Indications — covered when criteria below are met

Covered when criteria below are met

Establishing genetic diagnosis: Genetic testing to establish a genetic diagnosis of a mitochondrial disorder may be considered medically necessary when signs and symptoms of a mitochondrial disorder are present and genetic testing may eliminate the need for muscle biopsy.

Broader testing is appropriate for nonspecific phenotypes under guidance of a clinical geneticist/genetics counselor; single-gene or targeted multigene panels may be reasonable when phenotype and inheritance pattern are specific.

Targeted familial variant testing (preconceptional carrier testing): Targeted genetic testing for a known familial pathogenic variant in at-risk relatives may be considered medically necessary as preconceptional carrier testing when (1) there is a defined mitochondrial disorder in the family of sufficient severity to cause impairment of quality of life or functional status, and (2) a variant known to be pathogenic for that specific mitochondrial disorder has been identified in the index case.

At-risk relatives include only female relatives for mtDNA pathogenic variants and both male and female relatives for nuclear DNA pathogenic variants.

inv-02: Investigational / Not Medically Necessary — Not covered when

Not covered when

Investigational: Genetic testing for mitochondrial disorders is considered investigational and not medically necessary in all situations when the criteria for medical necessity are not met.

There is insufficient evidence to support general health outcomes or benefits for testing outside the stated indications.

inv-03: Medically Necessary Indications — Covered when clinically indicated for symptomatic individuals or for targeted familial variant testing:

Covered when clinically indicated for symptomatic individuals or for targeted familial variant testing:

Diagnostic genetic testing for symptomatic individuals: Genetic testing, including next-generation sequencing (NGS) of the mitochondrial genome, is appropriate as a first-line or comprehensive test to diagnose mtDNA disorders because it improves analytic sensitivity for point mutations, low-level heteroplasmy, and deletions and can obviate the need for muscle biopsy.

NGS is described as the new gold standard; reported diagnostic yield for NGS panels ranges roughly 15%–25% depending on population.

Targeted familial variant testing: Targeted testing for a known pathogenic familial variant is clinically valid and may impact reproductive decision making and clinical management for at-risk family members.

Clinical validity is expected to be high assuming analytic validity for the targeted assay.

inv-04: Covered procedures when medically necessary — Covered when medically necessary:

Covered when medically necessary:

Procedure codes: Coverage applies to the listed procedure codes when medically necessary: 81479, 0614U, 81401, 81403, 81405, 81406, 81440, 81460, 81465.

Identification of a code does not alone denote coverage; coverage requires documentation that medical necessity criteria are met and is subject to member benefit terms.

Genetic testing for mitochondrial disorders is considered investigational for any indication that does not meet the specific medical necessity criteria outlined in this policy. The policy states: “Genetic testing for mitochondrial disorders is considered investigational in all other situations when the criteria for medical necessity are not met.”

There are currently no specific disease‑modifying therapies for mitochondrial disorders that alter the natural history; treatment is primarily supportive. Genetic testing is therefore used for diagnosis, risk assessment, and management planning but is not itself a therapeutic intervention.

Policy history shows prior administrative edits and updates to terminology and coding, but these entries do not introduce explicit additional exclusions. The documented policy revisions reflect administrative and consensus reviews rather than new blanket exclusions.

The policy explicitly states that when the medical necessity criteria are not satisfied, genetic testing is investigational and not medically necessary. This applies to all situations not covered by the medical necessity provisions described in the policy.

The document identifies tests as “covered when medically necessary.” By designation, procedures that do not meet medical necessity requirements are not covered under this policy; coverage is contingent on meeting the stated clinical criteria and member benefit terms.

Covered Indications and Testing Scenarios

inv-33: Diagnostic genetic testing when signs/symptoms present and testing may obviate need for muscle biopsy — single-gene or multigene panels may be appropriate

Diagnostic genetic testing is covered when signs/symptoms are present and testing may obviate need for invasive tissue biopsy:

Clinical presentation: Individual has signs and/or symptoms consistent with a mitochondrial disorder such that genetic testing could establish the diagnosis and potentially eliminate the need for muscle (or other tissue) biopsy.

Providers should document relevant clinical findings and family history to support testing.

Appropriate test selection: When phenotype is highly suggestive of a specific mitochondrial disorder and inheritance pattern supports it, single-gene testing or targeted multigene panels for pathogenic variants specific to that disorder are appropriate.

If the phenotype is nonspecific or broader analysis is required, multigene panels or mitochondrial genome sequencing may be appropriate under genetics specialist guidance.

mtDNA vs nDNA considerations:

Coding: Procedure and Diagnosis Codes

Covered when medically necessaryCPTCovered

81479	Unlisted molecular pathology procedure
0614U	Proprietary lab code listed
81401	Molecular pathology procedure, tier 1 (example grouping from doc)
81403	Molecular pathology procedure, tier 2 (example grouping from doc)
81405	Molecular pathology procedure (listed)
81406	Molecular pathology procedure (listed)
81440	Mitochondrial DNA sequencing; full genome
81460	Exome sequencing, interpretation and report (listed)
81465	Trio exome sequencing or additional molecular procedure (listed)

Relevant ICD-10-CM DiagnosesICD-10

E88.40	Mitochondrial metabolism disorder, unspecified
E88.41	MELAS syndrome
E88.42	MERRF syndrome
E88.43	Disorders of mitochondrial tRNA synthetases
E88.49	Other mitochondrial metabolism disorders
E88.82	Obesity due to disruption of MC4R pathway
G31.82	Leigh's disease
H49.811	Kearns-Sayre syndrome, right eye
H49.812	Kearns-Sayre syndrome, left eye
H49.813	Kearns-Sayre syndrome, bilateral

1–10 of 14

1/2

Covered CPT/HCPCS Codes (listed as covered when medically necessary)mixedCovered

81479
0614U
81401
81403
81405
81406
81440
81460
81465

ICD-10-CM Diagnosis Codes (associated with covered testing)ICD-10

E88.40	Mitochondrial metabolism disorder, unspecified
E88.41	MELAS syndrome
E88.42	MERRF syndrome
E88.43	Disorders of mitochondrial tRNA synthetases
E88.49	Other mitochondrial metabolism disorders
E88.82	Obesity due to disruption of MC4R pathway
G31.82	Leigh's disease
H49.811	Kearns-Sayre syndrome, right eye
H49.812	Kearns-Sayre syndrome, left eye
H49.813	Kearns-Sayre syndrome, bilateral

1–10 of 14

1/2

Heteroplasmy threshold

Clinical implicationClinical expression of an mtDNA variant generally depends on exceeding a tissue-specific heteroplasmy threshold (i.e., symptoms appear when the percentage of mutated mtDNA copies in the affected tissue exceeds a threshold).

Quantitative rangeHeteroplasmy is expressed as a percentage ranging from 0% to 100% (document does not specify a numeric threshold value).

Tissue specificityThresholds are tissue-specific — level of mutated mtDNA required for clinical signs may differ between blood, muscle, or other tissues.

Diagnostic relevanceDetection and interpretation of heteroplasmy influence the choice of specimen and testing method (e.g., tissue-based testing when blood may miss heteroplasmy).

Provider Actions and Documentation Requirements

Prior Authorization

Medical necessity: diagnostic and targeted familial testing

Genetic testing to establish a genetic diagnosis of a mitochondrial disorder may be considered medically necessary when signs and symptoms of a mitochondrial disorder are present and genetic testing may eliminate the need for muscle biopsy; targeted testing of a known familial pathogenic variant in at‑risk relatives may be considered medically necessary as preconceptional carrier testing when (1) a defined mitochondrial disorder in the family is of sufficient severity to impair quality of life or function, and (2) a variant known to be pathogenic for that disorder has been identified in the index case.

Prior Authorization

Prior authorization / coding note

Selected molecular/genetic procedure codes are listed in the coding section; identification of a code does not denote coverage—coverage applies when services are medically necessary and is subject to the member's benefit terms and any prior authorization requirements.

See coding list for example codes: 81479, 0614U, 81401, 81403, 81405, 81406, 81440, 81460, 81465

Eligibility Requirements

A documented three‑generation family history can help determine the likely mode of inheritance: maternal transmission suggests mtDNA involvement, whereas Mendelian or X‑linked patterns suggest nuclear DNA (nDNA) causes. Family history information is an important eligibility consideration when selecting targeted testing strategies.

When collecting eligibility information, clinicians should use a three‑generation pedigree to evaluate inheritance patterns: exclusive maternal transmission supports mtDNA testing, while autosomal dominant, autosomal recessive, or X‑linked patterns support consideration of nDNA testing or nuclear gene panels.

Background and Definitions

Mitochondrial disorders result from pathogenic variants in either mitochondrial DNA (mtDNA) or nuclear DNA (nDNA) and typically affect high‑energy tissues such as the central nervous system, heart, and skeletal muscle. Clinical expression of mtDNA variants is influenced by heteroplasmy (the proportion of mutated mtDNA in cells), and diagnosis is often challenging because symptoms are nonspecific; molecular testing can reduce the need for invasive muscle biopsy.

Heteroplasmy — definition

DefinitionPresence of a mixture of mutated and wild-type mitochondrial DNA (mtDNA) copies within a cell or individual, expressed as a percentage (0%–100%).

Clinical significanceClinical symptoms generally appear once the proportion of mutated mtDNA exceeds a threshold amount in the affected tissue.

MeasurementReported as percentage of mtDNA molecules carrying the variant; analytic sensitivity depends on testing method and specimen.

Inheritance patterns — definition

Not Covered / Investigational

Genetic testing for mitochondrial disorders that does not meet the policy’s medical necessity criteria is considered not covered (investigational). The policy ties coverage to meeting clinical criteria and to the listed procedure codes, reinforcing that services lacking documented medical necessity will be denied.

Gene transfer and other gene‑based therapies for mitochondrial disease are experimental and at an early stage; they are not established, disease‑modifying treatments and are not considered covered interventions within the scope of this policy.

Within the portions of the document cited, there are no additional explicit tests or indications listed as definitively not covered beyond the general investigational stance for services not meeting medical necessity criteria.

Provider Guidance (Quick Reference)

Actions / Requirements

Note

Coding / Testing Notes

Revision History

2026-04-01Administrative updateLatest

Added code 0614U as part of new code process, effective 04/01/2026.

2025-09-24Administrative update

Removed Benefit Variations section and updated Disclaimer.

2025-07-22Consensus review

Policy Summary

PayerCapital Bluecross

PolicyGenetic Testing for Mitochondrial Disorders

Policy CodePolicy MP 2.273

Change TypeMinor / No material clinical changes

Effective DateApr 1, 2026

Last ReviewMar 12, 2026

Next Review DateApr 1, 2026

SourceLink

On This Page

For presentations suggestive of mtDNA involvement, consider sequencing of the mitochondrial genome; if multiple mtDNA deletions or suspicion for nuclear gene causes exist, consider nuclear gene panels covering known mitochondrial disease genes.

Choice of testing modality depends on suspected variant type and clinical context.

inv-34: Targeted testing for a known familial pathogenic variant in at-risk relatives as preconceptional carrier testing — coverage limited to families with defined disorder and known pathogenic variant

Targeted familial testing is covered for preconceptional carrier evaluation when specific family criteria are met:

Family disorder and index case: There is a defined mitochondrial disorder in the family of sufficient severity to cause impairment of quality of life or functional status, AND a variant known to be pathogenic for that specific disorder has been identified in the index case.

Documentation of the index case variant and information about disease severity should be provided.

At-risk relatives scope: Targeted testing is limited to at-risk relatives: only female relatives when the familial pathogenic variant is in mtDNA; both male and female relatives when the familial pathogenic variant is in nuclear DNA.

This distinction follows mtDNA maternal transmission versus autosomal/nuclear inheritance patterns.

inv-35: Symptomatic individuals with signs/symptoms suggestive of mitochondrial disorder — NGS mtDNA genome sequencing and targeted tests appropriate depending on syndrome

Symptomatic individuals with clinical features suggestive of mitochondrial disease:

Use of NGS mtDNA genome sequencing: NGS mitochondrial genome sequencing is appropriate as a first-line comprehensive test for mtDNA disorders because it improves sensitivity for point mutations, low-level heteroplasmy, and deletions.

NGS may be performed on blood, urine, or tissue depending on presentation and sample availability.

Additional targeted testing: Targeted tests (point mutation assays, deletion/duplication analysis) or nuclear gene panels may be appropriate depending on the suspected syndrome and variant type.

If panel testing is nondiagnostic, consider whole exome sequencing per cross-referenced policy MP 2.324.

inv-36: Asymptomatic close relatives for targeted testing when a familial pathogenic variant is known — Testing can inform reproductive decision making and management.

Asymptomatic close relatives may be covered for targeted testing when a familial pathogenic variant is known:

Known familial pathogenic variant: A pathogenic variant has been identified in a close relative (index case), and targeted testing for that specific variant is requested for an asymptomatic at-risk relative.

Testing can inform reproductive decision making and management in families with a severe mitochondrial disorder.

Clinical utility: Targeted testing is clinically useful to inform reproductive planning and potential clinical management for at-risk relatives.

Clinical validity for targeted testing is expected to be high assuming analytic validity of the test.

inv-37: Diagnostic testing for mitochondrial disorders associated with listed ICD-10 codes (e.g., MELAS, MERRF, Leigh disease, Kearns-Sayre)

Diagnostic testing is associated with the following ICD-10-CM diagnoses (examples listed):

Associated diagnoses: Coverage applies when testing is supported by an appropriate ICD-10 diagnosis such as E88.40 (mitochondrial metabolism disorder, unspecified), E88.41 (MELAS), E88.42 (MERRF), G31.82 (Leigh's disease), H49.811–H49.819 (Kearns-Sayre syndrome variants), and related codes.

Claims must include an appropriate diagnosis code consistent with medical necessity; see coding table for full list.

inv-38: Carrier and preconception/procreative genetic testing for females (Z31.430, Z31.438)

Carrier and preconception/procreative genetic testing for females may be covered when clinically indicated:

Encounter codes for procreative management: Coverage for carrier and preconception/procreative genetic testing should be supported by appropriate encounter codes such as Z31.430 or Z31.438 when testing is for procreative management.

Testing for procreative management should still meet the policy's familial and pathogenic-variant criteria for targeted testing.

Billing Rule

Coverage tied to listed procedure codes

Coverage applies to the CPT/HCPCS procedure codes listed in the policy when the service is medically necessary; documentation demonstrating medical necessity is required to support coverage for those codes.

Procedure codes listed as “Covered when medically necessary” include 81479, 0614U, 81401, 81403, 81405, 81406, 81440, 81460, 81465

Step Therapy

When panels are non‑diagnostic: consider whole exome sequencing

If targeted panels are non‑diagnostic (do not identify a causal variant), consider whole exome sequencing as the next diagnostic option (see cross‑reference to MP 2.324 Whole Exome and Whole Genome Sequencing for Diagnosis of Genetic Disorders).

Note

Testing approach: NGS as first‑line for comprehensive mtDNA analysis

Next‑generation sequencing (NGS) methodologies are described as the new gold standard for mtDNA genome sequencing and may be considered as a first‑line approach for comprehensive mtDNA analysis, with specimen choice (blood, urine, tissue) determined by symptom presentation and sample availability.

Documentation Required

Document genetic counseling by qualified individual

Document genetic counseling in the medical record and include evidence that counseling was provided by an individual with experience and expertise in genetic medicine and genetic testing methods.

Counseling should address benefits, harms, and potential impact on family members.
Record the counselor's qualifications or role (e.g., genetic counselor, clinical geneticist) when possible.

Billing Rule

Include appropriate ICD‑10 diagnosis code on claims

Include an appropriate ICD‑10 diagnosis code from the policy's listed mitochondrial disorder or related family‑history/testing encounter codes on claims to support medical necessity for testing.

Example diagnosis codes: E88.40, E88.41, E88.42, E88.43, G31.82, Z31.430, Z31.438, Z84.81

Documentation Required

Document a policy‑listed ICD‑10 diagnosis to support medical necessity

Providers should document an ICD‑10 diagnosis from the policy (for example, E88.40, E88.41, G31.82, Z31.430, Z84.81) in the medical record to support medical necessity for genetic testing.

Denial Risk

Denial risk: investigational when criteria unmet

Genetic testing is considered investigational and would be denied when the criteria for medical necessity in this policy are not met.

Denial Risk

Coverage contingent on member eligibility and benefit terms

Payment and processing of claims are subject to the member's benefit program terms, eligibility on the date of service, and a determination that the services are medically necessary and appropriate.

Denial Risk

Medical necessity requirement for listed tests

Tests in the coding section are listed as “Covered when medically necessary”; absence of documented medical necessity may result in claim denial.

Documentation Required

Use genetics specialist guidance; document counseling

Broader testing strategies and selection of appropriate tests should be guided by a clinical geneticist and genetics counselor; formal genetic counseling is recommended and should be documented.

Note

Ordering clinician scope: no specialist restriction stated

The policy does not restrict which clinician may order testing in these sections; no explicit ordering‑provider type requirements are specified.

Maternal inheritance

A maternal-only transmission pattern (affected women transmit to children; affected men do not) suggests the variant is in mtDNA.

Mendelian patternsFamily histories consistent with autosomal dominant, autosomal recessive, or X-linked inheritance suggest variants in nuclear DNA (nDNA).

De novo possibilityDe novo pathogenic variants (new mutations not present in parents) are also possible and should be considered in evaluation.

Next-generation sequencing (NGS) — definition

DefinitionNext-generation sequencing (NGS) refers to massively parallel sequencing methods used for comprehensive mtDNA and nuclear gene analyses.

Analytic advantagesNGS provides improved reliability and sensitivity for detecting point mutations, low-level heteroplasmy, and deletions compared with older methods.

Clinical recommendationNGS is described as the new gold standard for mtDNA genome sequencing and is appropriate as a first-line or comprehensive diagnostic test in many cases.

Laboratory-developed test (LDT) — definition

DefinitionLaboratory-developed test (LDT): a clinical laboratory test developed and validated in-house and offered as a laboratory service.

Regulatory standardLDTs must meet Clinical Laboratory Improvement Amendments (CLIA) general regulatory standards and laboratories offering LDTs must be licensed by CLIA for high-complexity testing.

FDA statusThe document notes that, to date, the U.S. Food and Drug Administration has chosen not to require regulatory review of these tests.

MELAS — definition / example

TermMELAS — mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes.

ICD-10 codeListed in policy as ICD-10-CM code E88.41 associated with covered testing.

Clinical contextMELAS is an example of a defined mitochondrial syndrome for which genetic testing may be indicated as part of diagnostic evaluation.

Consensus review with no change to policy stance.

2024-08-30Administrative update

New ICD code E88.82 was added and made effective.

2024-12-16Minor review

Policy language revised to again include statement that genetic testing may eliminate the need for muscle biopsy; no coding changes.

2023-11-17Consensus review

Consensus review with no change to policy stance; references updated.

2023-10-01Administrative update

New diagnosis code E88.43 added to policy from new code review; new code 0417U was added as medically necessary.

2022-10-19Minor review

Removed phrase 'and genetic testing may eliminate the need for muscle biopsy' from criteria and adjusted carrier testing language; updated guidelines, background, and references.

2021-09-22Consensus review

Consensus review with no change to policy statement; references and FEP updated.

2020-04-27Consensus review

Consensus review; wording changed from 'preconceptual' to 'preconceptional' with no change in policy intent; guidelines, background, references, and coding updated.