Forensic Biology & DNA: Foundations

This mock covers the foundational concepts every first-year MSc Forensic Science student must know about forensic biology, serology, and DNA profiling. Thirty questions across bloodstain pattern analysis (passive drops, transfer, spatter, area of origin), blood-group serology and the standard presumptive (Kastle-Meyer, luminol) and confirmatory (Takayama, Teichmann) tests, body-fluid identification (saliva amylase, semen acid phosphatase and PSA / p30, sperm morphology, vaginal mRNA markers), hair examination (anatomy, growth phases, the limits of microscopic comparison), DNA structure and Mendelian inheritance, the polymerase chain reaction and STR analysis on capillary electrophoresis, the full DNA-typing workflow from extraction to mixture deconvolution, the architecture of CODIS and the current Indian DNA-database position, and the special-purpose markers — Y-STRs for paternal lineage and mitochondrial DNA for degraded or hair-shaft samples.

It is pitched at BSc and first-year MSc forensic-science students at NFSU, LNJN-NICFS, and other Indian universities, FACT and FACT Plus aspirants, and UGC-NET candidates who need the Forensic Biology fundamentals locked in before tackling the application-level and casework papers.

Themes covered:

• Bloodstain pattern classification — passive, transfer, spatter, cast-off
• Directionality, angle of impact (arcsin W/L), and area of origin reconstruction
• Presumptive vs confirmatory blood tests — Kastle-Meyer, luminol, Takayama, Teichmann
• ABO and Rh serology, and the secretor status concept
• Saliva amylase (Phadebas), semen acid phosphatase and PSA / p30, Christmas Tree sperm staining
• Vaginal-fluid identification by glycogen cytology and tissue-specific mRNA
• Hair anatomy (cuticle / cortex / medulla), growth phases (anagen / catagen / telogen), and DNA recovery
• DNA structure, chromosomes, Mendelian inheritance, polymorphism, non-coding STR loci
• PCR cycle (denaturation / annealing / extension), capillary electrophoresis, stutter and drop-out
• DNA workflow — extraction, qPCR quantitation, multiplex amplification, detection, interpretation
• Mixture interpretation and probabilistic genotyping (STRmix, TrueAllele, EuroForMix)
• CODIS architecture (LDIS / SDIS / NDIS) and the current Indian DNA-database position
• Y-STR paternal-lineage typing, mtDNA inheritance, heteroplasmy

Each question carries a detailed 220+ word explanation citing standard references — Saferstein's Criminalistics, James & Nordby's Forensic Science, Butler's Fundamentals and Advanced Topics in Forensic DNA Typing, Goodwin / Linacre / Hadi's Introduction to Forensic Genetics, James, Kish & Sutton on bloodstain pattern analysis, and the FBI / CODIS public documentation. Allow 15 minutes; the explanations are long enough to use as study notes by themselves. If you can pass this mock comfortably, you have the FACT Forensic Biology vocabulary that the application-level papers build on.