OBJECTIVETo determine the genome structure of human telomeric repeat binding factor 1 (TERF1) and its pseudogenes.

METHODSSequences were obtained from GenBank and analyzed using the BLAST program and other relevant biology program (Sequencher, DNA Strider and Autoassembler, etc) to determine the genome and pseudogenome structure of TERF1. PCR and sequencing were performed to verify the results.

RESULTTERF1 gene which mapped to 8q13 was divided into 10 exons. It had four processed pseudogenes located on chromosome 13, 18, 21 and X respectively (Psi TERF1-13 Psi TERF1-18 Psi TERF1-21 and Psi TERF1-X ). They were entire intronless TERF1 genes which lacked some exons. Three homologous fragments of at least 60 kb on the flanking region of Psi TERF1-13, Psi TERF1-18 and Psi TERF1-21, respectively were noted.

CONCLUSIONTERF1 gene has 10 exons. It has four processed pseudogenes which are located on chromosome 13, 18, 21, and X, respectively. Large homologous fragments that belong to the recently duplicated segments are transchromosomal duplications.