Identification of two novel mutations in TRPS1 gene in families with tricho-rhino-phalangeal type I syndrome.

BACKGROUND

Autosomal dominant tricho-rhino-phalangeal syndrome I (TRPS I) is due to mutations in the TRPS1 gene. Tricho-rhino-phalangeal syndrome I is characterized by peculiar face and skeletal anomalies. Cone-shaped epiphyses are the characteristic radiographic findings.

OBJECTIVE

To describe 2 families with TRPS I and 2 novel mutations in the TRPS1 gene.

PATIENTS

The study included 2 nonrelated families with TRPS I. All exons of the TRPS1 gene were analyzed from genomic DNA.

RESULTS

The TRPS1 gene mutation analysis showed in family 1 the c.978C>A nonsense mutation within exon 4 and in family 2 the c.164A>C missense mutation within exon 3.

CONCLUSIONS

We found 2 families with TRPS1 caused by 2 novel mutations in the TRPS gene, particularly a missense mutation in exon 3, outside the GATA zinc finger domain, that leads a mild TRPS phenotype. Our data show a higher genotypic spectrum in the TRPS I and demonstrate that mutations in the amino terminus of the transcription factor result in TRPS I syndrome.