GJB2-Related
Severe to profound loss from changes in both copies of GJB2, which makes connexin 26, a protein linking the supporting cells around the hair cells. It’s the most common genetic cause of hearing loss present from birth, and it often appears in families where both parents have normal hearing. Depending on the exact changes it can be anywhere from mild to profound; severe to profound, shown here, is the most common. Cochlear implants usually work well. A gene therapy for it entered its first human trial in August 2026.
Summary
- Severity
- Severe89 dB HL
- Most loss at
- 6 kHz · 100 dB
Degree of the worse ear, averaged over all eight frequencies, on the scale used by U.S. audiologists (ASHA)
Pure-tone average (PTA)
- Left ear
- 83dB
- Severe
- Right ear
- 83dB
- Severe
What’s a pure-tone average?
Pure-tone average is the quietest tone each ear can just hear, averaged across three pitches central to speech (500 Hz, 1 kHz, and 2 kHz). It’s the single number U.S. audiologists use to sum up an audiogram. 15 dB or lower is normal hearing, and every 10 dB higher means sounds need to be about twice as loud to be heard. Internationally, the World Health Organization averages four pitches, adding 4 kHz, so where high pitches have more loss its number comes out higher.
Thresholds by frequency
| Hz | L | R |
|---|---|---|
| 250 | 70 | 70 |
| 500 | 75 | 75 |
| 1k | 85 | 85 |
| 2k | 90 | 90 |
| 3k | 95 | 95 |
| 4k | 95 | 95 |
| 6k | 100 | 100 |
| 8k | 100 | 100 |