Electronic Medical Records now act as main repositories for patient data. As we con- tinue to explore the intricate relationship between phenotype and genotype, these records become a vital source for monitoring patients’ progression of disease. The pre- sence of a given variation, as it relates to the appearance or absence of disease over time, can be mapped as encounters are recorded by clinicians. Every result, encounter, event, or diagnosis is recorded as a data item and includes a date. This rich longitudi- nal data provide trends that show improvement or decline in state and occurrence or absence of diagnostic criteria and can be used to guide.
