The application provides a CYP21A2
gene mutation detection method,
system and storage medium, comprising the following steps: identifying difference sites and homologous intervals by
reference genome self alignment, and constructing a paralog characteristic site
fingerprint library; constructing a Masker
reference genome according to the homologous intervals on the
reference genome, and obtaining a candidate variation
list; using the physical link information of a double-end sequencing read pair and the characteristic site
fingerprint library to determine the true or false
gene source of each candidate variation; quantitatively calculating the true
gene copy number based on re-alignment sequencing depth, background reference
library and characteristic site
allele frequency; and determining whether a recombination event occurs between the true gene and the false gene based on the physical link information of the double-end sequencing read pair across multiple characteristic sites. The application effectively distinguishes different copy states such as
gene deletion,
single copy, normal double copy and duplication, and assists in clinically determining
gene deletion or duplication events.