A novel mechanism for variable phenotypic expressivity in Mendelian diseases uncovered by an AU-rich element (ARE)-creating mutation

Background Variable expressivity is a well-known phenomenonin which patients with mutations in one gene display varying degrees of clinical severity, potentially displaying only subsets of the clinical manifestations associated with the multisystem disorder linked to the gene. This remains an incompletely understood phenomenonwith proposed mechanisms ranging from allele-specific to stochastic.