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The CPT® Code 81252 pertains to the molecular genetic testing of the GJB2 gene, which encodes the gap junction protein beta 2, also known as connexin 26. This testing is specifically aimed at identifying mutations within the full gene sequence that are responsible for nonsyndromic hearing loss (NSHL). The GJB2 gene plays a critical role in the formation of gap junctions, which are essential for cellular communication, allowing the transport of nutrients, ions, and signaling molecules between adjacent cells. Connexin 26, the protein produced by the GJB2 gene, is particularly important in the inner ear (cochlea) and the epidermis. Located on chromosome 13, the GJB2 gene has been associated with at least 90 identified mutations that can lead to a form of deafness known as NFNB1, which is inherited in an autosomal recessive manner. In this context, an individual who inherits one mutated copy of the gene will be a carrier, while inheriting two mutated copies will result in the manifestation of the condition. The mutations typically disrupt the process by which sound waves are converted into nerve impulses, leading to hearing impairment. Full gene sequence testing, as indicated by CPT® Code 81252, is essential for a comprehensive understanding of the genetic factors contributing to NSHL. In contrast, testing for known familial variants, which may include specific deletions such as 35delG or 30delG, is reported under CPT® Code 81253. These deletions are particularly prevalent in certain populations, with 35delG and 30delG being more common among Caucasians, while 235delC is frequently observed in Asian populations, and 167delT is often found in Ashkenazi Jewish individuals. All these mutations result in the production of an abnormally small protein that fails to effectively bridge the functional gap between cells, leading to hearing loss. Additionally, some mutations may alter amino acids, resulting in unstable or dysfunctional proteins that cannot form proper gap junctions. Another form of hearing loss, DFNA3, is inherited in an autosomal dominant manner and is caused by the replacement of one amino acid with another, where inheriting just one mutated gene is sufficient to cause the disease.
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The molecular genetic testing for the GJB2 gene is indicated for individuals who are suspected of having nonsyndromic hearing loss (NSHL). This testing is particularly relevant for:
The procedure for conducting the GJB2 gene analysis involves several key steps:
After the GJB2 gene analysis is completed, patients may receive genetic counseling to discuss the results and their implications. If a mutation is identified, the patient may be advised on potential next steps, including family planning options or further testing for family members. It is also important for patients to understand the nature of their condition, including the autosomal recessive or dominant inheritance patterns associated with the identified mutations. Follow-up appointments may be scheduled to monitor any changes in hearing or to provide additional support and resources as needed.
| Short Descr | GJB2 GENE FULL SEQUENCE | Medium Descr | GJB2 GENE ANALYSIS FULL GENE SEQUENCE | Long Descr | GJB2 (gap junction protein, beta 2, 26kDa, connexin 26) (eg, nonsyndromic hearing loss) gene analysis; full gene sequence | Status Code | Statutory Exclusion (from MPFS, may be paid under other methodologies) | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 9 - Not Applicable | Multiple Procedures (51) | 9 - Concept does not apply. | Bilateral Surgery (50) | 9 - Concept does not apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 9 - Concept does not apply. | Co-Surgeons (62) | 9 - Concept does not apply. | Team Surgery (66) | 9 - Concept does not apply. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | CLIA Waived (QW) | No | APC Status Indicator | Service Paid under Fee Schedule or Payment System other than OPPS | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | T1H - Lab tests - other (non-Medicare fee schedule) | MUE | 1 | CCS Clinical Classification | 234 - Pathology |
| 90 | Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number. | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | GA | Waiver of liability statement issued as required by payer policy, individual case | GW | Service not related to the hospice patient's terminal condition | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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| 2014-01-01 | Changed | Code description changed. |
| 2013-01-01 | Added | Added. Also changed the semicolon after 26KDa to a comma per AMA corrections document. |
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