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		Objective: Through this research we intended to block Tbx2expression using antisense oligonucleotides and to observe the morphological effects that Tbx2blocking has on developing mouse vibrissa pads (whisker pads). Background: Summary of Follicle Development:Hair follicle induction begins around stage 21, or 13 days post coitus (dpc). The first visible marker of a site that will become a hair follicle is the placode, a condensation of mesoderm underneath a small symmetric invagination of epidermis (Oro, 575; Hardy, 55). The morphogenesis of hair is dependent on epithelium-mesenchyme interactions (Hardy, 55; Moore, 308; Gat, 605; Chiang, 1). Hair follicle development can be generally summarized as a two step process. The first step is initiation and induction. This step involves determining cell fate, and determining pattern formation, which determines the number and the spacing of the placodes (Moore, 308, Kashiwagi, 22). Initially this first step begins when a mesenchymal signal instructs the ectoderm to form a placode (Gat, 605; Chiang, 1). Next, the ectoderm produces a signal that initiates formation of a mesenchymal dermal structure, called the dermal papilla (Gat, 605, Hardy, 56). During this is stage the epithelium forms a column of cells which penetrates the mesenchyme, while the mesenchyme ensheaths the column; it is this aggregate that will be incorporated into the dermal papilla (Moore, 309;