Abstract: The present disclosure provides an additive for PCR amplification, a multiplex PCR amplification kit, and use thereof, wherein the additive comprises benzalkonium bromide. The additive, when added to a simplex PCR system or a multiplex PCR system, can provide great promoting effects on the amplification efficiency and specificity of the simplex PCR amplification or multiplex PCR amplification, and thus possess great application prospects in simplex PCR or multiplex PCR.

Abstract: The present disclosure discloses a method, a device and a system for detecting chromosomal aneuploidy. The method comprises: sequencing at least a portion of a nucleic acid in a sample under test to obtain a sequencing result including reads; aligning the reads to a first reference sequence to obtain an alignment result including specific chromosomes to which the reads are mapped; determining, for a first chromosome, the amount of reads mapped to the first chromosome based on the alignment result; and comparing the number of the reads mapped to the first chromosome with the amount of reads in a negative control mapped to the first chromosome to determine the number of the first chromosome. When the method is employed to detect chromosomal aneuploidy, the detection results acquired have relatively high sensitivity and accuracy.

Abstract: A sequencing method comprising: (i) combining a template nucleic acid having a first optical detection label at the end with a primer to obtain a first complex; (ii) imaging the first complex to obtain a first image; (iii) mixing the first complex, polymerase, and one or more of nucleotides with a optical detection label to obtain an extension product by polymerization reaction; (iv) imaging the extension product to obtain a second image; (v) removing the cleavable group of the nucleotides with the optical detection label from the extension product to obtain a second complex; (vi) repeating the above steps (ii) to (v) once or more times to determine the template nucleic acid sequence. The sequencing method can achieve single molecule sequencing by capturing template nucleic acids through primers.