Application of SNaPshot Technology in Semen-Specific cSNP Genetic Marker.

Objectives: To explore the feasibility of genetic marker detection of semen-specific coding region single nucleotide polymorphism (cSNP) based on SNaPshot technology in semen stains and mixed body fluid identification.

Methods: Genomic DNA (gDNA) and total RNA were extracted from 16 semen stains and 11 mixtures composed of semen and venous blood, and the total RNA was reverse transcribed into complementary DNA (cDNA). The cSNP genetic markers were screened on the validated semen-specific mRNA coding genes. The cSNP multiplex detection system based on SNaPshot technology was established, and samples were genotyped by capillary electrophoresis (CE).

Results: A multiplex detection system containing 5 semen-specific cSNPs was successfully established. In 16 semen samples, except the cSNP located in the gene showed allele loss in cDNA detection results, the gDNA and cDNA typing results of other cSNPs were highly consistent. When detecting semen-venous blood mixtures, the results of cSNP typing detected were consistent with the genotype of semen donor and were not interfered by the genotype of venous blood donor.

Conclusions: The method of semen-specific cSNPs detection by SNaPshot technology method can be applied to the genotyping of semen (stains) and provide information for determining the origin of semen in mixed body fluids (stains).