Connexin 26 Mutations Test: Booking, Price, and Results
About Connexin 26 Mutations Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | GJB2 Gene Mutation Test, GJB2 Sequencing, Connexin 26 Sequencing, DFNB1 Testing, Cx26 Mutation Analysis |
| Sample Type | Whole blood (EDTA tube) |
| Fasting Required | No fasting required |
| Report Time | 25 days |
| Recommended For | All ages and genders; particularly recommended for newborns who fail hearing screening and individuals with a family history of hearing loss |
| Price | Starting at ₹8,700 |
What is a Connexin 26 Mutations Test?
The Connexin 26 mutations test is a molecular genetic test that checks for changes (mutations) in the GJB2 gene. This gene provides instructions for making connexin 26, a protein that plays a key role in hearing. Doctors order this test to investigate unexplained hearing loss, especially in newborns and children. It is also known as the GJB2 Gene Mutation Test or GJB2 Sequencing. A small blood sample is collected from a vein and analysed in a laboratory using Next Generation Sequencing (NGS).
What Does a Connexin 26 Mutations Test Measure?
This test examines the GJB2 gene to identify variants that may cause hearing problems. The table below explains the key elements of the test analysis.
| Component | What It Means |
|---|---|
| GJB2 gene mutations | Checks for changes in the gene that provides instructions for connexin 26 protein production |
| Connexin 26 protein function | This protein helps move potassium ions between cells in the inner ear, which is essential for the brain to process sound |
| Gap junction activity | Connexin 26 forms channels between cells; mutations can disrupt this communication and impair hearing |
| Common Indian variants | Includes 35delG, W24X (frequently found in the Indian population), 167delT, 235delC, and other known pathogenic changes |
The result is reported as the mutation status of the GJB2 gene, categorised as negative, carrier, or affected.
Why is a Connexin 26 Mutations Test Done?
This test is ordered when genetic causes of hearing loss need to be identified. It helps clinicians understand the underlying reason for hearing problems and guides decisions about management and family planning.
Common Symptoms That May Require This Test
The following symptoms or situations commonly prompt a doctor to recommend this test.
- Hearing loss detected at birth or early infancy
- Failed newborn hearing screening
- Unexplained sensorineural hearing loss (inner ear or nerve-related hearing loss)
- Speech and language delay in a child
- Progressive hearing difficulties without a clear cause
- Strong family history of hereditary hearing loss
Conditions This Test Can Help Detect
This test can help identify the following conditions.
- DFNB1A (autosomal recessive nonsyndromic hearing loss): the most common genetic cause of congenital hearing loss, occurring when a child inherits two mutated copies of the GJB2 gene
- Syndromic hearing loss with skin disorders: including Vohwinkel syndrome, Bart-Pumphrey syndrome, keratitis-ichthyosis deafness syndrome, and palmoplantar keratoderma (thickened skin on the palms and soles)
- Carrier status: identifies individuals who carry one mutated copy of the gene, which is important for family planning
How to Prepare and What to Expect
No special preparation is needed for the Connexin 26 mutations test procedure. The steps below explain what happens from booking to receiving your report.
Do You Need to Fast?
No, fasting is not required. This test analyses DNA, which is unaffected by food or drink. You can eat and drink normally before the test.
Practical Tips Before Your Test
The following tips will help ensure your visit goes smoothly.
- Bring a detailed clinical history, including your symptoms, previous test results, and family history, as this is required for the test
- Carry any previous hearing test reports (audiograms) if available
- Inform the laboratory staff of any family members who have been diagnosed with hearing loss
- Wear a short-sleeved or loose-sleeved top to allow easy access to your arm for blood collection
- Genetic counselling before and after testing is recommended to help you understand the implications of the results
Step-by-Step Procedure
- A trained phlebotomist cleans the inside of your elbow with an antiseptic wipe.
- A small amount of blood (approximately 2 ml) is drawn from a vein using a fine needle into an EDTA tube (a purple-topped tube that prevents clotting).
- The sample is labelled and stored at 2 to 8 degrees Celsius for safe transport to the laboratory.
- In the laboratory, DNA is extracted from your blood, and the GJB2 gene region is amplified and analysed using NGS (Next Generation Sequencing).
- Molecular geneticists examine the results to identify any mutations and classify them.
- A detailed report is prepared and sent to you digitally, typically within 25 days.
Factors That Can Affect Accuracy
The following factors may influence the reliability of your result.
- Poor sample quality due to improper collection or storage
- Insufficient clinical history was provided at the time of testing
- Variants of uncertain significance (VUS), which require additional clinical correlation
- Rare mutations outside the scope of standard gene coverage
Understanding Your Connexin 26 Mutations Test Results
Your report will indicate the mutation status of the GJB2 gene. The table below outlines the possible result categories.
| Result Category | What It Means |
|---|---|
| No pathogenic variants detected | No GJB2 mutations found; this does not rule out other genetic or non-genetic causes of hearing loss |
| One pathogenic variant was detected | Carrier status: the individual has one mutated copy and is generally not affected, but can pass the mutation to children |
| Two pathogenic variants were detected | Affected status; associated with GJB2-related hearing loss or, in some cases, syndromic hearing loss with skin conditions |
| Variant of uncertain significance (VUS) | A change is found, but its clinical impact is unclear; further clinical correlation is needed |
These ranges are general guidelines. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
How to Maintain Healthy Levels
Because this is a genetic test, the result does not change with lifestyle. However, the following steps are important after receiving your result.
- Early identification of GJB2-related hearing loss allows timely fitting of hearing aids or cochlear implants, which can greatly support speech and language development.
- Genetic counselling is strongly recommended when mutations are found, especially for couples planning a family.
- Regular audiological follow-up is advisable even when hearing loss appears mild, to monitor any changes over time.
Lupin Diagnostics Connexin 26 Mutations Test Price and Home Collection
The Connexin 26 mutations test is available at Lupin Diagnostics starting at ₹8,700, with home sample collection offered across major Indian cities. City-wise prices are listed below for reference.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 8700 |
| CHENNAI | 8700 |
| HYDERABAD | 8700 |
| KOLKATA | 8700 |
| NAVI MUMBAI | 8700 |
| PUNE | 8700 |
Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred time slot.
- Opt for home sample collection by a certified phlebotomist, or visit your nearest Lupin Diagnostics centre.
- Receive your report via email or WhatsApp within the stipulated turnaround time.
Home Collection
Connexin 26 mutations test home collection is available across cities. A trained phlebotomist visits your home at your chosen time to collect the blood sample. All samples are processed in NABL-accredited laboratories, and your digital report is accessible within 25 days of sample collection.
Frequently Asked Questions
Connexin 26 is a protein produced by the GJB2 gene. It forms communication channels between cells in the inner ear and helps recycle potassium ions, a process that is essential for converting sound into signals the brain can understand. Mutations in this gene can disrupt this process and lead to hearing loss.
GJB2 mutations account for approximately 19.4% of nonsyndromic hearing loss cases in the Indian population. The W24X and 35delG mutations are the most frequently identified variants in India. This makes the Connexin 26 mutations test particularly relevant for Indian patients with unexplained hearing loss.
When both parents each carry one mutated copy of the gene, there is a 25% chance with each pregnancy that the child will inherit both copies and have hearing loss. There is a 50% chance the child will be a carrier, and a 25% chance the child will inherit no mutation. A genetic counsellor can provide a personalised risk assessment for your family.
Not necessarily. A negative result means no mutations were found in the GJB2 gene specifically. Hearing loss can be caused by mutations in more than 85 other genes. Your doctor may recommend additional genetic testing if hearing loss is present and this test is negative.
The genetic mutation itself cannot be corrected. However, hearing loss caused by GJB2 mutations can be effectively managed with hearing aids or cochlear implants. Early testing and diagnosis are important because timely intervention supports better speech and language development in children.
Prenatal diagnosis may be possible for families where a specific pathogenic or likely pathogenic variant has already been identified. It is not available for variants of uncertain significance. Families with known mutations are advised to speak with a genetic counsellor before conception or early in pregnancy to discuss their options.
The report is typically available within 25 days of sample collection. This time is needed for DNA extraction, sequencing, and expert analysis. Lupin Diagnostics will send your report digitally once it is ready.
Connexin 26 Mutations Test: Booking, Price, and Results
