The connective tissue serves as a medium for transmitting the genetic code and exerting an influence on the properties of the overlying epithelial tissue. Concrete evidence implies connective tissue plays a significant role in influencing the keratinization process of the overlying epithelium. Epithelial keratinization following a coronally advanced flap with connective tissue graft is also governed by environmental factors in addition to inherent potential within the graft. Differences in gene expression profiles may vary from individuals, teeth and among sites.