Virtually no SIGN represents a specific SIGNAL.
A group of SIGNS may be interpreted as a single or as multiple SIGNALS.
A SIGN is inherently objective in contrast to signals which are hypothetical interpretations.
A SIGNAL may point to a particular or multiple pathogeneses pathways and etiologies.
Pathogenesis (expression of an etiology) can reflect a variety of causes (etiologies).
Etiology can manifest in a variety of clusters of SIGNS (clinical variability).
Etiology can impact diverse patho-genesis pathways causing diverse signals (pleiotropism).
Etiology is generally categorized as Mendelian (single gene mutations) – cytogenetic – environmental or teratogenic if impacting development – and multifactorial.