Highly sensitive human Y-specific fluorescent PCR-assay to detect extremely low and degraded male DNA in sexual assault

Abstract To determine presence of male cells in trace evidence is one of the critical parts in conviction of a crime especially in a sexual assault. A confirmatory test of semen is relied upon identification of sperm. Several approaches such as cytology, proteins, Y-DNA, RNAs and epigenetics have been developed. Among those, the most stable biological components are cells and DNA. In sparseness or absence of cell, DNA is a popular method-of-choice at present. The purposes for Y-DNA analysis are either for personal identification or detection of male cells, however, low copy number of DNA may likely produce a partial profile that is unable to identify a perpetrator. Thus, the concept of this study is to develop a simple PCR assay to detect male DNA with highly sensitivity and specificity and is applicable to a sample with degraded DNA condition. The assay can detect Y-DNA in as low as ten haploid or five diploid cells and in female DNA mixture of at least 1:100. It also effective in a sperm-negative casework.