As is known, H-Y antigens (male specific minor histompatibility antigens) are a group of minor histocompatibility antigens encoded on the Y-chromosome with homologous H-X antigens on the X-chromosome. H-Y antigens were originally discovered as transplant antigens, and they are only expressed in male individuals without specificity for different tissues and organs. A lot of research results show that H-Y antigens play an important role in the sex selection and identification. The paper reviews the above and discusses the application prospect of H-Y antigen in forensic science.

Source identification of human biological materials in crime scene plays an important role in reconstructing the crime process. Searching specific genetic markers to identify the source of different human biological materials is the emphasis and difficulty of the research work of legal medical experts in recent years. This paper reviews the genetic markers which are used for identifying the source of human biological materials and studied widely, such as DNA methylation, mRNA, microRNA, microflora and protein, etc. By comparing the principles and methods of source identification of human biological materials using different kinds of genetic markers, different source of human biological material owns suitable marker types and can be identified by detecting single genetic marker or combined multiple genetic markers. Though there is no uniform standard and method for identifying the source of human biological materials in forensic laboratories at present, the research and development of a series of mature and reliable methods for distinguishing different human biological materials play the role as forensic evi-dence which will be the future development direction.

Objective To explore the feasibility of detecting of Y-STR of fetal DNA in m aternal plasm a using Ion Torrent PGMTM System . Methods A total of 16 fetal DNA sam ples from m aternal plasm as (8 cases from 38 w eeks gestational age and 8 ones from 12 w eeks) w ere prepared and a m ultiplex assay w ith 7 STR loci (DYS390,DYS391,DYS393,DYS438,DYS437,DYS456,DYS635) w as designed for m ul-tiplex-PC R am plification. U sing Ion Torrent PGMTM System , the results of Y-STR sequences and capillary electrophoresis w ere obtained and com pared. Results Y-STR specific alleles w ere detected in the m ater-nal plasm a of all the pregnant w om en having m ale babies of second and third trim ester, w hich w ere higher than that detected by capillary electrophoresis. C onsistent Y-STR genotypes w ere observed betw een fetal DNA from m aternal plasm a and genom ic DNA from the new born babies. Conclusion B ased on Ion Torrent PGMTM System , the prenatal Y-STR detection m ethod m ay provide a high-sensitive and high-throughput choice for prenatal STR detection in forensic testing.

H um an violent behavior is a com plex behavior w hich is influenced by genetic and environ-m ental factors. T here is a trend in investigating the m echanism of violent behavior by using the genetic m ethods. T his article review s several candidate genes and advances in epigenetics w hich are associated w ith violent behavior. T he prospects and significance of violent behavior research from the view of gene polym orphism and epigenetics are also discussed.

Objective To develop a multiplex allele-specific PCR (AS-PCR) assay with three-color fluo-rescence labeling for mitochondrial DNA (mtDNA) SNP typing. Methods Based on the principle of AS-PCR, the primer sets were designed for 20 SNP located on the coding region of mtDNA and divided in-to 2 groups labeled with FAM and HEX fluorescence, respectively. A primer set included two forward (reverse) allelic specific primers with different sizes and a generic reverse (forward) primer. Blood sam-ples from 200 unrelated individuals were analyzed by AS-PCR and capillary electrophoresis. Three ran-dom samples at least for each SNP site were examined and verified by direct sequencing. The haplotype frequency was investigated. Results Distinct electropherograms of 200 blood samples were obtained suc-cessfully. The typing results of direct sequencing were identical to those obtained from AS-PCR. The minimum detectable DNA concentration was 0.2 pg under the system of 10μL. The sensitivity of the DNA concentrations ranged from 0.5 to 5 pg. The 200 individuals were assigned into 15 haplotype, and the haplotype diversity was 0.906 0. Conclusion AS-PCR is a simple, rapid and efficient method for mtDNA SNP typing, and can be applied to forensic practice.

Objective To explore the change rules of peak area ratio of STR loci to Amelogenin (AMEL) locus (STR/A M EL ), a sex-determ ining gene in DNA degradation, and to evaluate the application of STR/A MEL value in the estim ation of DNA degradation degree. Methods DNA w as extracted from iliopsoas, and the variations of STR/A MEL value (Penta E/AMEL, Penta D/AMEL, FGA/AMEL) w ere analyzed after the artificial degradation w as m ade by DNaseⅠ, and the changes of these three ratios of the iliopsoas naturally degraded in an outdoor environm ent w ere also analyzed. The regression curves w ere analyzed using the periods of DNA degradation and outside the body as the independent variable (x) and the STR/A MEL value as the dependent variable (y) and three curve equations under tw o conditions w ere established. Results B oth under the conditions of artificial and natural degradation, STR/A MEL value had a negative relationship w ith the degradation tim e. The relationship betw een STR/A MEL and degradation tim e can be w ell sim ulated by the cubic function. R2 w as over 0.99 under controlled degradation condition and over 0.86 under natural degradation condition. Conclusion The STR/A MEL value (Penta E/AMEL, Penta D/AMEL , FGA/AMEL ) is negatively related w ith the DNA degradation degree, w hich follow s m athem atical regression m odels strictly, and it m ight be applied to evaluate the DNA degradation degree.

There are two kinds ofamelogeningene mutation, including mutation in primer-binding re-gion ofamelogeningene and micro deletion of Y chromosome encompassingamelogeningene, and the latter is more common. The mechanisms of mutation in primer-binding region ofamelogeningene is nu-cleotide point mutation and the mechanism of micro deletion of Y chromosome encompassingamelo-geningene maybe non-allelic homologous recombination or non-homologous end-joining. Among the population worldwide, there is a notably higher frequency ofamelogeningene mutations in Indian popu-lation, Sri Lanka population and Nepalese population which reside within the Indian subcontinent. Thoughamelogeningene mutations have little impact on fertility and phenotype, they might cause incor-rect result in gender identification. Using composite-amplification kit which including autosomal STR lo-cus,amelogeningene locus and multiple Y-STR locus, could avoid wrong gender identification caused byamelogeningene mutation.

Objective To establisha multiplex STR genotyping m ethod for autosom al STR and Y-STR loci in forensic biological practice. Methods W idely used autosom al STR loci and Y-STR loci w ere se-lected. A set of PC R prim ers w as designed, and a 5-dye fluorescent labeled STR multiplex PC R reagent kit w as developed. Results A kit w as developed w hich can sim ultaneously detect 15 autosom al STR loci, 10 Y-STR loci, and an Amelogenin. Conclusion The 15 autosom al STR plus 10 Y-STR kit in com bination w ith capillary electrophoresis m ethod w as used to STR genotyping w ith accurate and reli-able results. The new one-step testing kit can potentially be w idely used in forensic cases and D N A databank in the future.

Objective To establish a rapid method for the detection of SMCY antigen. Methods To Use the technology of colloidal gold immunochromatography with double antibody sandwich assay, the gold labeled pad was coated with colloidal gold labeled SMCY rabbit polyclonal antibody, colloidal gold strip was made for detection of serum, which include 12 serum samples of pig, cattle, dog, chicken and mice and 50 serum samples of human. Results The colloidal gold test strips showed obvious specificity in human and common animal sera and could distinguish between male and female sera. Conclusion This method can be used to identify the serum of women and men, and has certain species specificity, which provides a direction for forensic science to rapidly identify gender of human samples.

Objective To evaluate the potential application of separating smoking individuals from non-smoking ones by DNA methylation profiles from peripheral blood. Methods Human genome-wide DNA methylation data were downloaded from NIH GEOdata base. DNA methylation values from certain CpG sites were used to evaluate their significance between smokers and non-smokers by Student's T Test, as well as the clustering analysis. Results There are significant DNA methylation between smokers and non-smokers for certain CpGs. Conclusion Detection of methylation status from human peripheral blood can distinguish smokers from non-smokers.