Study links craniofacial anomalies to kidney disease
LONDON, UK: New research has suggested that polycystin-2 (PKD 2), a protein encoded by the PKD 2 gene whose mutations have been associated with autosomal dominant polycystic kidney disease (ADPKD), may play a critical role in craniofacial development and growth. Scientists found that people with the kidney disease also had characteristic dental and facial anomalies.
In a thorough examination of mice, researchers from King’s College London identified particular dental and facial abnormalities in PKD 2 mutant mice. Among other features, they found signs of mechanical trauma, such as fractured molar roots, distorted incisors, alveolar bone loss and compressed temporomandibular joints. In addition, they had abnormal skull shapes. According to the researchers, the mice showed no indication of any of these phenotypes at embryonic stages, however. This indicates that PKD 2 affects the structure of the face by influencing jaw strength and other features, they stated.
Since such facial anomalies had never been identified in patients with ADPKD, the researchers analysed 3-D photographs of the faces of 11 female and 8 male patients, with a mean age of 48. “Surprisingly, this analysis revealed specific characteristics of ADPKD patient faces, some of which correlated with those of the mutant mice,” said Prof. Paul Sharpe, an expert in craniofacial development and stem cell biology at the institute. For instance, the patients had a slight vertical lengthening of their faces, slightly longer noses and less symmetrical faces.
Sharpe concluded that further studies are needed to determine whether the analysis of dental and facial features could be used to diagnose such diseases.
The study was carried out in collaboration with the Cambridge Institute for Medical Research, University College London and the Nantes University Hospital in France. The findings were published online on 5 February in the Human Molecular Genetics journal ahead of print.