Fingerprint Fundamentals
This is the most common fingerprint pattern class in the general population, accounting for 60%–65% of all human prints.
What is a Loop?
In modern and legacy DNA labs, this step is performed first to break open biological cells and isolate pure DNA strands.
What is Extraction?
This chemical process is used in modern forensic labs to make millions of copies of target STR loci from small evidence samples.
What is PCR (Polymerase Chain Reaction)?
When the Yekaterinburg mass grave was excavated in 1991, anthropologists determined only 9 bodies were present, meaning this many execution victims were missing.
What is 2 (Prince Alexei and Princess Anastasia/Maria)?
In federal database standards like CODIS, this exact number of core STR loci is currently examined to establish an official match in court.
What is 20 Core Loci?
If an imaginary line drawn between two deltas touches or crosses central core ridges, the whorl is classified as this specific type.
What is a Plain Whorl?
These biological "molecular scissors" are used during RFLP profiling to cut extracted DNA strands into smaller fragments at specific base sequences.
What are Restriction Enzymes?
Forensic DNA fragments move toward the positive electrode (+) during gel electrophoresis because of the net negative charge carried by this chemical group.
What is the Sugar-Phosphate Backbone?
Forensic anthropologists determine whether a skeleton belongs to an individual over or under 22 years old by checking for the degree of eruption in these teeth.
What are Wisdom Teeth?
Rather than sealed plastic Ziploc sandwich bags that trap moisture and destroy DNA, wet biological evidence must always be packaged in this type of container.
What is a Breathable Paper Bag (or Box)?
This is the formal term for the study of the uniqueness of friction ridge structures and minutiae points for personal identification.
What is Ridgeology?
In legacy RFLP profiling, this X-ray film output displays radioactive probes as a visual "barcode" band pattern for suspect comparison.
What is an Autoradiogram?
During gel electrophoresis, these types of STR fragments experience less friction weaving through agarose pores, moving the fastest and furthest down the gel.
What are Shorter STR fragments (fewer repeat units)?
All five Romanov children inherited 100% of their mitochondrial DNA (mtDNA) strictly from this royal parent.
Who is Tsarina Alexandra?
Damp or wet biological crime scene evidence should never be stored in airtight plastic Ziploc bags because trapped moisture causes this issue.
What is bacterial/fungal mold growth that degrades DNA strands?
To classify whorl patterns, an examiner draws an imaginary line between these two triangular ridge structural points.
What are Deltas?
In the 1983–1986 Narborough Murders case, this 17-year-old became the world's first person exonerated by forensic DNA profiling after falsely confessing.
Who is Richard Buckland?
At a crime scene, hair evidence yields an STR profile that includes this locus, showing X and Y bands to indicate a male donor.
What is the AMEL (Amelogenin) locus?
This living British royal family member provided the maternal reference mtDNA used to confirm the identity of Tsarina Alexandra and her daughters.
Who is Prince Philip (Duke of Edinburgh)?
To prevent cross-contamination at a crime scene, separate items like bloody fabric and cigarette butts must always be collected and stored in this manner.
What is separately in individual, labeled containers?
Matching a fingerprint pattern class (like a Loop) is only class evidence; an examiner must compare these specific ridge characteristics to establish a 100% individual match.
What are Minutiae Points (or Ridge Characteristics)?
This killer attempted to cheat the world's first police DNA dragnet by paying a coworker (Ian Kelly) to take his blood test for him.
Who is Colin Pitchfork?
Under this foundational rule of DNA interpretation, if a suspect matches crime scene evidence across 19 core loci but differs at just 1 single locus, they are 100% excluded as the donor.
What is the Rule of Exclusion?
Forensic scientists conclusively proved that claimant Anna Anderson was NOT Princess Anastasia, but rather this Polish factory worker, using tissue mtDNA.
Who is Franziska Schanzkowska?
Modern forensic laboratories analyze hyper-variable non-coding STR regions for CODIS profiles rather than coding genes for this main reason.
What is to identify individuals uniquely without revealing private personal/medical genetic traits?