title: Determination of variations in gene expression during fracture healing.
abstract: The genetic make-up and physiological state of a cell or tissue in an organism interact to determine the level at which specific genes are expressed. Identifying genes differentially expressed between 2 genetic or physiological states often gives insight into the molecular mechanisms controlled by the process in question. Various methods have been devised to identify differentially expressed genes and to quantify the expression of differentially regulated genes at the RNA or protein level. These methods are most accurate when the experimental samples are derived from highly controlled and reproducible sources, such as cultured cells. However, no simple in vitro models have been developed to study all biological processes and some are still best studied in the context of the whole organism. Using bone fracture healing as a model, we quantified the expression of 2 housekeeping and 2 regulatory genes during this complex biological process to determine the statistical parameters required to study differential gene expression in tissue samples derived from entire organisms. Our analysis shows that 5 samples in each group are needed to identify genes differentially expressed by a factor of 3 between 2 physiological or genetic states.
authors.affiliation: Department of Orthopaedics, UMDNJ-New Jersey Medical School and Graduate School of Biomedical Sciences, 185 South Orange Avenue, Newark, NJ 07103, USA.
authors.forename: Gregor
authors.initials: G
authors.lastname: Balaburski
authors.forename: J Patrick
authors.initials: JP
authors.lastname: O'Connor
mesh_terms: D000818:Animals; D017931:DNA Primers; D017102:Fracture Healing / Q000235:genetics*; D015870:Gene Expression; D014644:Genetic Variation; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018401:Sample Size
chemical_list: D017931:DNA Primers