title: Semen searching when sperm is absent.
abstract: Sexual assault cases have varying factors that may mask semen findings when analysing evidence at the forensic laboratory. Semenogelin (Sg) is a potential marker for the identification of semen even at azoospermy or when few sperm cells are found. The current study examined Sg in normospermic and azoospermic donors as an internal evaluation of sensitivity, specificity and interference. The impact of a historical review of 53 judicial sexual assault cases over a five-year period was also analysed. The use of varying tests was of importance to prioritize certain samples within cases. Semen findings by Sg were then compared to prostate-specific antigen (PSA), phosphatase enzyme (AP) and Y-chromosome presence, the latter being used in an attempt to link semen fluid identification with obtaining a male DNA profile. Test findings were the highest ever registered for Sg (1:400,000), PSA (1:800,000), AP (1:25,000) and sperm cytology (SC) (1:50,000). Our results demonstrated the usefulness of using the Sg marker to avoid a false semen-negative result (6% cases), particularly in cases where sperm was absent or scarce (11% spermatozoa positive cases). Results were expressed in categories according to the set: Sg-PSA-AP. Thus, categories I (full positive, 46%), VI (full negative, 27%) and III (Sg/PSA positive; 11%) were the most frequent and Y-chromosome was obtained in 59%, 12% and 12% ratios, respectively. In conclusion, Sg was recommended for the workflow procedure of semen investigation when sperm absence is expected either from azoospermic/oligospermic or normospermic semen, especially before/after ejaculation.
authors.affiliation: National Institute of Toxicology and Forensic Science INTCF, Biology Service, José Echegaray, 4 Las Rozas, 28232 Madrid, Spain. Electronic address: pilarm.fernandez@justicia.es.
authors.forename: Pilar
authors.initials: P
authors.lastname: Martínez
authors.affiliation: National Institute of Toxicology and Forensic Science INTCF, Biology Service, José Echegaray, 4 Las Rozas, 28232 Madrid, Spain.
authors.forename: Begoña
authors.initials: B
authors.lastname: Santiago
authors.affiliation: National Institute of Toxicology and Forensic Science INTCF, Biology Service, José Echegaray, 4 Las Rozas, 28232 Madrid, Spain.
authors.forename: Belén
authors.initials: B
authors.lastname: Alcalá
authors.affiliation: National Institute of Toxicology and Forensic Science INTCF, Biology Service, José Echegaray, 4 Las Rozas, 28232 Madrid, Spain.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Atienza
mesh_terms: D000293:Adolescent; D000328:Adult; D000469:Alkaline Phosphatase / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D041322:Chromosomes, Human, Y; D049429:Forensic Pathology; D006801:Humans; D008297:Male; D017430:Prostate-Specific Antigen / Q000032:analysis; D011902:Rape; D012661:Semen / Q000737:chemistry*; D029607:Seminal Vesicle Secretory Proteins / Q000032:analysis*; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D015415:Biomarkers; D029607:Seminal Vesicle Secretory Proteins; C424482:seminal vesicle-specific antigen; D000469:Alkaline Phosphatase; D017430:Prostate-Specific Antigen
keywords: Azoospermy; Semenogelin; Sexual assault; Sperm; Y-chromosome