The investigators will enroll and perform whole exome sequencing on two cohorts of patients. One cohort will consist of two hundred newborns with no known conditions whose parents will be recruited during the mother's pregnancy. The second cohort will include two hundred infants and children up to the age of five years with diagnosed conditions including conditions detected through standard newborn screening such as phenylketonuria and other inborn errors of metabolism, hearing loss and other rare conditions that may fit criteria for newborn screening in the future.