Figure 4.

Schematic representation of the multistep process starting from a rare Mendelian disease such as PXE and subsequent identification of the causal gene(s). From then, a combination of technological approaches is performed in several model systems to gain insights into cellular signaling. This knowledge can already be of relevance for common disorders, which show an overlap with the phenotype of the rare disease, but can also be used for development of innovative treatments, which benefit patients of both orphan and complex disorders [20, 21, 46–54].