OBJECTIVETo identify potential mutation of TRAPPC2 gene in a Chinese family affected with X-linked spondyloepiphyseal dysplasia tarda (X-SEDL), and explore its underlying molecular mechanism.

METHODSPeripheral blood samples were collected from 32 members of the family and 50 healthy adults to extract genomic DNA. DNA sequences of exons 3 to 6 and their exon/intron boundaries were amplified with PCR amplification. Direct bi-directional sequencing analysis was performed on the PCR products. The sequences were aligned to the reference sequences from the GenBank to determine mutation site and type.

RESULTSA nucleotide substitution of the splice-donor in TRAPPC2 intron 3, c.93+5G>A, was detected in the proband, but no sequence change was detected in TRAPPC2 exons 3 to 6. All of the 6 male patients and 8 female carriers from the family were detected to have carried this mutation. The same mutation was not found in the remaining 18 family members with a normal phenotype and 50 healthy controls.

CONCLUSIONWe have detected a c.93+5G>A mutation in the TRAPPC2 gene in a Chinese family affected with X-SEDL. Our results have expanded the spectrum of TRAPPC2 mutations and is helpful for presymptomatic and prenatal diagnoses of this disease.