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Carrier Screening for Genetic Diseases Policy Number: PG0442 ADVANTAGE | ELITE | HMO Last Review: 07/25/2019

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Carrier Screening for Genetic Diseases Policy Number: PG0442 ADVANTAGE | ELITE | HMO Last Review: 07/25/2019 Carrier Screening for Genetic Diseases Policy Number: PG0442 ADVANTAGE | ELITE | HMO Last Review: 07/25/2019 INDIVIDUAL MARKETPLACE | PROMEDICA MEDICARE PLAN | PPO GUIDELINES This policy does not certify benefits or authorization of benefits, which is designated by each individual policyholder contract. Paramount applies coding edits to all medical claims through coding logic software to evaluate the accuracy and adherence to accepted national standards. This guideline is solely for explaining correct procedure reporting and does not imply coverage and reimbursement. SCOPE X Professional X Facility DESCRIPTION Carrier screening is testing asymptomatic individuals to identify those who are heterozygous for serious or lethal single-gene disorders with the purpose of informing the risk of conceiving an affected child. Risk-based carrier screening is performed in individuals having an increased risk based on population carrier prevalence, and personal or family history. Conditions selected for screening can be based on ethnicities at high risk (e.g., Tay- Sachs disease in individuals of Ashkenazi Jewish descent) or may be pan-ethnic (e.g., screening for cystic fibrosis carriers). Ethnicity-based screening for some conditions has been offered for decades and, in some cases, has reduced the prevalence of diseases. While methods for carrier screening of conditions individually may have been onerous in the past, contemporary molecular techniques including next-generation sequencing allow simultaneously identifying carriers of a wide range of disorders efficiently and inexpensively. Expanded carrier screening (ECS) involves screening individuals or couples for disorders in many genes (up to 100s). The disorders included may also span a range of disease severity or phenotype. Arguments for ECS include potential issues in assessing ethnicity, ability to identify more potential conditions, efficiency, and cost. However, there are possible downsides of screening individuals at low risk such as the consequences of screening for rare single-gene disorders in which the likely phenotype may be uncertain (e.g., due to variable expressivity and incomplete penetrance). Additionally, there are circumstances in which the condition screened may not have as accurate results with an expanded screening panel compared to current recommendations for screening (i.e. Tay- Sachs disease, Hemoglobinopathies).The list of conditions included in ECS panels is not standardized. Although ECS panels would include conditions assessed in risk-based screening, ECS panels include many conditions not routinely evaluated and for which there are no existing professional guidelines. For information regarding multi- gene panel testing, please refer to Medical Policy PG0453. POLICY Prior authorization is required for genetic testing unless otherwise noted in one of our policies. Some genetic testing requires prior authorization or may be non-covered. A provider must refer to the Paramount prior authorization list and specific medical policy in reference to specific tests for coverage determinations. Refer to these policies regarding genetic testing for carrier screening (this list may not be all-inclusive): PG0287 Cell-Free DNA Tests/Non-Invasive Prenatal Screening For Fetal Aneuploidy (81420, 81422, 81507, 0009M) PG0296 Comparative Genomic Hybridization (CGH) (81228, 81229, S3870) PG0355 Genetic Testing for Hereditary Thrombophilia (81240, 81241, 81291) PG0442 – 12/28/2020 PG0360 Genetic Testing for Fragile X-Related Disorders (81243, 81244) PG0387 Genetic Testing for Cystic Fibrosis (81220-81224) PG0398 Genetic Testing for Spinal Muscular Atrophy (81329, 81336, 81337) Direct-to-consumer (DTC) genetic testing is non-covered. For information regarding Multi-Gene Panel Testing, please refer to Medical Policy PG0453. Refer to CODING/BILLING INFORMATION below for coverage determination. COVERAGE CRITERIA HMO, PPO, Individual Marketplace, Elite/ProMedica Medicare Plan, Advantage Pre-test genetic counseling (as well as post-test genetic counseling) is recommended when considering genetic testing related to carrier status. Documentation of pre-test genetic counseling is required for coverage of carrier screening. Pre-test genetic counseling should address the following topics (ACMG, 2008): A general description of the disorder(s) offered in the carrier screen Discussion of variable expressivity and incomplete penetrance if applicable Discussion of residual risk in light of a negative screening result A description of what it means to be a “carrier” Carrier screening is voluntary; Informed consent must be obtained. Informed consent includes discussion of confidentiality, discrimination (i.e. discussion of the Genetic Information Non-Discrimination Act, and applicable state laws), potential psychosocial issues, and economic considerations. Post-test genetic counseling should address the following topics with a positive carrier screening result: Discussion of findings- what the individual is a carrier of, description of the condition, and discussion of risk to fetus or future pregnancies Possible reproductive options Implications for family members; encouragement to share information with family members Post-test genetic counseling should address residual risk after a negative carrier screening test. If obstetric care providers are uncomfortable providing genetic counseling related to carrier screening, referral to a certified genetics professional (such as a genetic counselor) is warranted. Preconception or prenatal carrier testing for Cystic Fibrosis (CF) with a targeted mutation analysis (23-25 mutations) as recommended by the American College of Medical Genetics (ACMG) is considered medically necessary for a parent or prospective parent. Please see PG0387 for further details regarding genetic testing for Cystic Fibrosis. Preconception or prenatal carrier testing for Spinal Muscular Atrophy (SMA) is considered medically necessary for a parent or prospective parent. Please see PG0398 for further details regarding genetic testing for Spinal Muscular Atrophy. Preconception or prenatal carrier testing through a panel carrier test that includes the below conditions is considered medically necessary for a parent or prospective parent of Ashkenazi Jewish (also known as Eastern European/Central European Jewish) descent (defined as having at least one grandparent who is Ashkenazi Jewish). Cystic Fibrosis Familial Dysautonomia Tay-Sachs disease Fanconi anemia (Group C) PG0442 – 12/28/2020 Niemann-Pick disease (Type A) Bloom syndrome Mucolipidosis IV Gaucher disease (Type 1) Familial hyperinsulinism Glycogen storage disease (Type 1) Joubert syndrome (type 2) Maple syrup urine disease (type 1B) Usher syndrome (Type 1F and 3) For All Other Carrier Screening Tests In order to determine the clinical utility of gene test(s), all of the following information must be submitted for review: 1. Name of the genetic test(s) or panel test 2. Name of the performing laboratory and/or genetic testing organization (more than one may be listed) 3. The exact gene(s) and/or mutations being tested 4. Relevant billing codes 5. Medical records related to the genetic test History and physical exam Conventional testing and outcomes Conservative treatment provided, if any Carrier testing for genetic diseases is considered medically necessary when ONE of the following criteria is met: The individuals have a previously affected child with the genetic disease One or both individuals have a first- or second-degree relative who is affected One individual is known to be a carrier One or both individuals are members of a population known to have an allele frequency of ≥1% One or both individuals has had abnormal or inconclusive biochemical or hematologic screening for a genetic condition (such as Tay-Sachs disease [beta-hexosaminidase A enzyme activity] or Alpha- Thalassemia [complete blood count, electrophoresis, etc]) AND ALL of the following criteria are met: The natural history of the disease is well understood and there is a reasonable likelihood that the disease is one with high morbidity and/or mortality in the homozygous or compound heterozygous state Alternative biochemical or other clinical tests to definitively diagnose carrier status are not available, or, if available, provide an indeterminate result or are individually less efficacious than genetic testing The genetic test has >90% detection rate to guide clinical decision making and residual risk is understood An association of the marker with the disorder has been established Individual has not previously received genetic testing for the disorder. Note: In general, genetic testing for a particular disorder should be performed once per lifetime; however, there are rare instances in which testing may be performed more than once in a lifetime (eg, previous testing methodology is inaccurate, a new discovery has added significant relevant mutations for a disease, significant changes in technology or treatments indicate that test results or outcomes may change as a result of repeat testing) Results of genetic testing will directly impact and change clinical management or assist with reproductive planning of the individual being tested Technical and clinical performance of the genetic test is supported by published peer-reviewed medical literature Testing is of a voluntary nature for the member and informed consent has been obtained and documented Paramount considers preimplantation genetic diagnosis not medically
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