The invention discloses methods and apparatuses for the detection and diagnostics of genetic alterations/mutations in a target sample, which may be a solid tissue or a bodily fluid. A reference sample is also acquired, and the target and reference samples are replicated into multiple target and reference replicates. The replicates are sequenced, and the sequence data is analyzed based on a statistical test. The statistical test compares the measurements between the target and reference replicates at respective allelic indices. True positive calls are then made based on the results of the statistical testing, and the desired genetic alterations/mutations are identified at the base-pair level. The invention may be used for diagnostics related to cancer, auto-immune disease, organ transplant rejection, genetic fetal abnormalities and pathogens.