Clinical Diagnosis of X-Linked Spondyloepiphyseal Dysplasia Tarda and a Novel Missense Mutation in the Sedlin Gene (SEDL)

Objective. Spondyloepiphyseal dysplasia tarda (SEDT) is a rare hereditary bone disease characterized by spinal and epiphyseal anomalies. We identified the disease by gene sequencing in a Chinese pedigree with SEDT. Methods. We extracted genomic DNA from five members of a four-generation Chinese SEDT kindred with three affected males and then analyzed the genetic mutation by PCR and DNA sequencing. Results. DNA sequencing showed that the genetic missense mutation occurred one bp upstream of exon 6 in the SEDL gene in two families, and a heterozygous mutation was found in a female carrier. In addition, no mutation was found in the other members of the family. Conclusion. SEDT in this family was caused by a G/C missense mutation in exon 6 of the SEDL gene, previously not shown to be associated with X-linked SEDT.