Top Banner
DNA MUGSHOTS AGAINST CRIME
30

DNA MUGSHOTS AGAINST CRIME

Aug 23, 2014

Download

Science

Pundlik Rathod

 
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1: DNA MUGSHOTS AGAINST CRIME

DNA MUGSHOTS

AGAINST CRIME

Page 2: DNA MUGSHOTS AGAINST CRIME

SPECIES COUNT…….

About 8.7 million species is the new estimated count of species on Earth

All are different from each other

WHY IT IS SO?

Page 3: DNA MUGSHOTS AGAINST CRIME

DNA(deoxyribonucleic acid)DNA is often called

the blueprint of life. (source code of

organism)DNA contains the

instructions for making proteins within the cell.

3

Page 4: DNA MUGSHOTS AGAINST CRIME

Double Strand of DNADNA is polymer of

nucleotides

Pentose sugar + Nitrogen Base + Phosphate Group = Nucleotide

4 4

Page 5: DNA MUGSHOTS AGAINST CRIME

Nitrogenous basesBase pairs as ADENINE-

THYMINE double hydrogen

bond

GUANINE- CYTOSINE

Triple hydrogen bond

Page 6: DNA MUGSHOTS AGAINST CRIME

DNA USED IN….In forensic department- DNA Fingerprinting or other

Criminal investigationsDetermining whether a biological material is of human

originStudying the genetic ancestry of human ie.Family tree(solve Property Crimes)Genetic modification of organisms (plant ,animal and

bacteria) eg. Agriculture Healthcare (genetically engineered vaccines)Gene therapy Cloning

Page 7: DNA MUGSHOTS AGAINST CRIME

TECHNOLOGY AGAINST CRIMEEye-witness Sketch of criminalsFingerprints CCTV camerasNARCO testDNA-fingerprinting

DNA mugshots

Page 8: DNA MUGSHOTS AGAINST CRIME

How DNA is Used to Solve Crimes?DNA is uniqueinvestigators collect DNA samples from crime

scenes eg. few drops of blood, hair or dandruff , weapon,

sweat,etc.Get genome sequence or genetic codeIf samples doesn't match the victim then..compare it to samples from possible suspects If a suspect has left DNA at the crime scene, they

are definitely tied to the crime.

Page 9: DNA MUGSHOTS AGAINST CRIME

USING technique of DNA MUGSHOTS…

Currently we can't go from DNA to a face or from a face to DNA, but it may be possible.

New Computer Program Creates 3D ‘FACE image' From DNA

Page 10: DNA MUGSHOTS AGAINST CRIME

MUGSHOTS FROM DNA

• Using genes to predict eye and hair colour is relatively easy.

• But the complex structure of the face makes it more valuable as a forensic tool — and more difficult to connect to genetic variation.

• 7000 different components of face are compared by software and guessed which gene will impact where.

Page 11: DNA MUGSHOTS AGAINST CRIME
Page 12: DNA MUGSHOTS AGAINST CRIME
Page 13: DNA MUGSHOTS AGAINST CRIME

WORKFLOW:A) Original surface, B) Trim non-face parts, C) Reflect mirror image, D) Anthropometric mask of landmarks, E) Remapped, F) Reflected remap, G) Symmetrized, H) Reconstructed

Page 14: DNA MUGSHOTS AGAINST CRIME

DNA PROFILING

A technique used by scientists to distinguish between individuals of the same species using only samples of their DNA

Page 15: DNA MUGSHOTS AGAINST CRIME

Stages of DNA ProfilingStage 1: Cells are broken down to release DNA

If only a small amount of DNA is available it can be amplified using the polymerase chain reaction (PCR)

Page 16: DNA MUGSHOTS AGAINST CRIME

Stages of DNA Profiling Step 2: The DNA is cut into fragments using restriction

enzymes.

Each restriction enzyme cuts DNA at a specific base sequence.

Page 17: DNA MUGSHOTS AGAINST CRIME

Stages of DNA ProfilingThe sections of DNA that are cut out are

called restriction fragments.

This yields thousands of restriction fragments of all different sizes because the base sequences being cut may be far apart (long fragment) or close together (short fragment).

Page 18: DNA MUGSHOTS AGAINST CRIME

Stages of DNA ProfilingStage 3:Fragments are

separated on the basis of size using a process called gel electrophoresis.

DNA fragments are injected into wells and an electric current is applied along the gel.

Page 19: DNA MUGSHOTS AGAINST CRIME

Stages of DNA Profiling DNA is negatively

charged so it is attracted to the positive end of the gel.

The shorter DNA fragments move faster than the longer fragments.

DNA is separated on basis of size.

Page 20: DNA MUGSHOTS AGAINST CRIME

Stages of DNA ProfilingA radioactive

material is added which combines with the DNA fragments to produce a fluorescent image.

A photographic copy of the DNA bands is obtained.

Page 21: DNA MUGSHOTS AGAINST CRIME

Stages of DNA ProfilingStage 4:The pattern of fragment distribution is then

analysed.

Page 22: DNA MUGSHOTS AGAINST CRIME

Stages of DNA Profiling

Page 23: DNA MUGSHOTS AGAINST CRIME

Issues

23

Based on case readings, doubts fall into the following themes:

(1) coincidental profile matches (2) unintentional attribution of DNA profile to

another(3) unfounded threats like planting of evidences and

eugenics (4) breadth of database.

Of these four, only the first can be deliberated within the world of “pure” science thereby crediting such doubts to DNA technology itself.

Page 24: DNA MUGSHOTS AGAINST CRIME

Issues

24

Coincidental Profile Match

In the cases reviewed for the past years , evidentiary samples from crime scenes are reported to be often incomplete or partial DNA profiles. Limited quantities of DNA can make it impossible to genotype at every locus (STR uses 13 loci as markers). In some instances, the test yields no information about the genotype at a particular locus; in some instances one of the two alleles at a locus will become undetectable.

Page 25: DNA MUGSHOTS AGAINST CRIME

Issues

25

Unintentional attribution of DNA profile to another

Unintentional attribution of DNA profile to another could be brought about by cross-contamination of samples, accidental transfer of DNA from one sample to another, mislabelling of samples, and misinterpretation of samples.

Page 26: DNA MUGSHOTS AGAINST CRIME

LimitationsDNA evidence is powerful, but it

does have limitations.•Fake DNA

Instances where criminals plant fake DNA samples at a crime scene

•High Tech lab

Page 27: DNA MUGSHOTS AGAINST CRIME

Skilled peoples Requiredplastic bags direct sunlight warmer conditions may damage DNA. so officers must be

skilled to handle biological materials.

Page 28: DNA MUGSHOTS AGAINST CRIME

AdvancementsNew testing procedures

RFLP( restriction fragment length polymorphism) analysis required large amounts of relatively high-quality DNA.

Newer procedures require far less DNA and can be completed faster.Source of DNA

 Science has devised ingenious ways of extracting DNA from sources that used to be too difficult or too contaminated to use

Page 29: DNA MUGSHOTS AGAINST CRIME

Expanding DNA databaseThe databases managed by the CODIS

(Combined DNA Index System) software continue to expand.

Justice officials estimate the new collecting requirements will add DNA from an additional 1.2 million people to the database each year 

Training To Investigators Crime labs have developed formal

protocols for handling and processing evidence, reducing the likelihood of contamination of samples

Page 30: DNA MUGSHOTS AGAINST CRIME

CONCLUSION

• DNA MUGSHOTS is the most sophisticated way to identify living organisms.•DNA cannot easily be altered once it is left at a crime scene which makes it a strong forensic tool.•laboratories carrying out DNA MUGSHOTS would perform the tests with the highest accuracy possible.