Identification of human ccn2*(connective tissue growth factor) promoter polymorphisms

Background-Connective tissue growth factor (CCN2; CTGF) is a newly identifi ed growth factor, which is involved in the regulation of wound repair and f ibrosis. Because there is variation among individuals with respect to tissu e response to injury, genetic factors might be involved in the final outcom e of tissue repair or scarring. For example, polymorphisms in the promoter region of genes, such as those encoding transforming growth factor beta1 (T GF-beta1), interleukin 10 (IL-10), and tumour necrosis factor alpha (TNF-al pha), influence transcriptional responses and are thought to contribute to the dysregulation of these genes in pathological conditions. Aim-To investigate whether the promoter region of the ccn2 (ctgf) gene cont ains polymorphic sequences that might account for differential expression. Materials/Methods-Seventy seven human DNA samples were sequenced - 45 were from healthy controls and 32 were from patients with ischaemic heart diseas e (IHD) - using M13 tailed sequence specific ccn2 (ctgf) primers for amplif ication of a 600 bp fragment upstream of the transcription start site. Ampl icons were bidirectionally sequenced with a dye primer M13 forward and reve rse sequencing kit. Results-A C to G substitution was identified at position -132 in one of the patients with IHD. Moreover, in five of the 32 patients with IHD and in si x of the 45 healthy controls, a G to C polymorphism was found at position - 447. These substitutions at -132 and -447 are thought to Lie within predict ed binding domains for the transcription factors Pbx-l and MZF1, respective ly. In addition, insertions at position -43 (G), -47 (C), -71 (G) and a C t o T substitution at position -198 were found in all DNA samples compared wi th the published ccn2 (ctgf) promoter sequence. These corrections do not in volve sequences predicted to function as transcription factor binding sites . Conclusion-Sequence analysis of the ccn2 (ctgf) promoter of 77 human DNA sa mples has revealed corrections and polymorphic sites. The latter Lie within putative regulatory elements.