1. Hair Analysis

2. What is Hair?

3. Hair= Appendage of skin Grows out of a hair follicle
Root, Shaft and Tip

4. Layers of Shaft

6. Cuticle Layer Tough and Resistant Outer Layer
Overlapping scales made of keratin
Used for species identification

8. Casting to see scale pattern

9. Cortex Region Beneath Cuticle
Contains pigment granules that give color to hair
Look at color, shape and distribution of granules

11. Medulla Region Center Region of Hair
Presence and pattern varies from person to person and from hair to hair on an individual
Uniserial
Multiserial
Vacuolated
Lattice
Fragmented Intermittent Continuous
Amorphous

12. Medulla Human hairs generally have Fragmented or Absent medulla
Exception:Mongoloid/Asian - usually have continuous medulla

14. Roots Necessary for growth of hair Can tell the growth stage of hair:
Anagen= Actively growing, root is flame shaped
Catagen= Slowed growth, root elongated and shrunken
Telogen= Hair growth ends, root club-shaped, hair falls out of follicle

15. Roots
Follicular Tissue
Catagen
Anagen
Telogen

16. Hair: Comparative Studies
Need comparative microscope
Need multiple hairs for comparison
Look at overall color, length and diameter
Medulla absent or present?
Distribution, shape, color intensity of pigment granules in cortex

17. Hair: Comparative Studies
Dyed Hair (Paint Roller)vs Natural?
Bleached Hair (Yellowish tint)
Time of Dyeing? (Hair grows 1cm/month)
Nits or fungal infections?

18. Hair: Comparative Studies
Types:
Scalp= uniform diameter and pigment distribution
Pubic= short, curly and diameter variations
Facial=Coarse, triangular, blunt tips

19. Hair: Comparative Studies
Race:
Black= Tight curls, dense uneven pigment distribution, flat to oval hair in cross section
Caucasian= Straight or wavy, fine to coarse pigments that are evenly distributed, oval to round hair in cross section

20. Hair: Comparative Studies
Age and Sex:
Age and Sex Determination= Most No,
Baby Hair short, thin and fine pigment

21. Hair: Comparative Studies
Forcibly Pulled Hair
See follicular tissue at root
Isolate Nuclear DNA
Telogen hairs not a good source for DNA
Mitochondrial DNA

22. Hair: Comparative Studies
Drug use/ Poisoning

23. Hair Collection Need control samples
Need at least 50 scalp hairs from an individual
Need at least 20 pubic hairs from an individual
Need full length hair

24. Cut close to scalp, need minimal amount of head and body hair