Table 3.
Clinical features of patients with the SLC26A7 mutations and with the SLC26A4 mutations (Pendred syndrome)
| SLC26A7 | Pendred syndrome (SLC26A4) | ||||
|---|---|---|---|---|---|
| Our study | Previous report | ||||
| Patient 1 | Patient 2 | Elder sister (43.1) | Younger sister (43.2) | ||
| Mutation | c.1498C > T | c.927_933delinsG | |||
| Zygosity | Homozygous | Homozygous | |||
| Amino acid change | p.Gln500Ter | p.Ile309_Glu311delinsMet | |||
| Thyroid | |||||
| Hypothyroidism* | Yes | Yes | Yes | Yes | Euthyroid in most patients |
| Goitre | Yes | Yes | Yes | No | 50–83% of the patients |
| Severity of hypothyroidism | Moderate | Severe | N.A. | N.A. | N.A. |
| Age at diagnosis of hypothyroidism | 15 days | 5 years | 3 years | N.A. | |
| High level of serum TG | Yes | Yes | N.A. | N.A. | Yes |
| Other Feature | |||||
| Renal tubular acidosis* | No | No | No | No | N.A. |
| Deafness | No | No | N.A. | N.A. | Yes |
| EVA | N.A. | N.A. | N.A. | N.A. | 80–100% of the patients |
| Impairment of gastric acid secretion* | N.A. | N.A. | N.A. | N.A. | N.A. |
TG, thyroglobulin; EVA, enlarged vertibular aqueduct; N.A., not available
*Phenotype of Slc26a7 knock out mice