The invention discloses a tiny residual focus detection method and
system based on ultra-high depth sequencing, and relates to the technical field of tiny residual focus intelligent detection.The tiny residual focus detection method comprises the following steps that on the basis of a sequencing
library, splitting is conducted according to a sample index to obtain a to-be-detected sample, and a
consensus sequence is obtained according to a molecular identifier of the to-be-detected sample; based on a
consensus sequence, filtering out the
consensus sequence of which the
mass value is less than 25 or the family size is less than 3, and combining a variation type and a distance from a fragment edge as
noise introduced into an original
nucleic acid molecular chain; a context sequence (context) and a chain direction are used as
noise for introducing the capture level of PCR amplification; on the basis of the
noise level, the
circulating tumor DNA level is estimated in combination with tumor priori knowledge, and the MRD state is determined by detecting the significance of molecular
signal sources. According to the invention, the sensitivity and specificity of MRD detection are improved.