The actions of these hormones such as estrogen, progesterone and catecholamines are executed through one or more of their respective receptors as estrogen receptors (ESRs), progesterone receptor (PGR) and adrenergic receptor (ADR) Allelic variants of ESR, PGR and ADR genes have been shown to be associated with susceptibility or progression with various disorders such as myocardial infarction [14], [15], cholesterol gallstones and biliary tract diseases [16]. Here, PGR is linked to biliary tract disorder.