Genetic analysis of skin wound healing and scarring in a porcine model

Contraction is a normal part of skin wound healing and wound closure; however, excessive contraction and severe scarring concern patients and physicians alike. The present study has investigated the degree and kinetics of wound contraction in a porcine model of wound healing, to elucidate the genetic and molecular basis for abnormal skin wound healing and scarring. Healing of excisional skin wounds in juvenile female Yorkshire pigs closely resembled normal healing in humans. In contrast, identical wounds in female red Duroc pigs contracted significantly more, forming hypercontracted, hyperpigmented scars. Yorkshire x red Duroc F1 animals healed without hyperpigmentation, but with significantly greater wound contraction than observed in either parent breed. To examine the genetic transmission of the hypercontractile phenotype, all F1 animals were bred to a single Yorkshire boar, generating 20 backcross animals. All backcross animals healed with significantly less contraction than the normal Yorkshire animals. These findings suggest that the genetic contribution to scar phenotype in this animal model is complex, with a limited number of major genes controlling wound contraction, and an unknown number of minor genes that appear to modulate the impact of the major genes.