Figure 1: Understanding the pathogenesis of the disease also stems from studies of familial primary biliary cirrhosis (PBC). Clues as to the pathogenesis of the disease are provided by population studies involving a large number of families of affected individuals and case reports (see also Table 1). These studies support the notion that the pathogenesis of the disease is complex, and that genes, epigenetic factors, and environment are mostly likely involved in concert rather than in isolation. The relative contribution of each of those factors is largely unknown and may vary among individuals and clusters. Their participation may be important for the induction of the immunopathological processes leading to PBC development, but may also be important for the progression of the disease towards a favourable slow pace or an unwanted progressive deterioration.