Distinguishing Male and Female Hair Characteristics by Light Microscopy : A Criminalistics Approach
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Abstract
Hair is one of the most frequently encountered types of trace evidence in forensic investigations. It assists in establishing a potential associative link among the suspect, victim, and the scene of crime. The morphological characteristics of hair can be useful in the majority of forensic cases. Current study employs the light microscopy techniques for examining and correlating the morphological characteristic differences between human male and female scalp hair. A compound comparison microscope (Olympus BX-53) equipped with polarizing and fluorescence attachments, along with a stereomicroscope (Olympus SZ-61), was used for hair examination. The objective of the present study was to examine and compare selected physical and microscopic features of male and female human scalp hair from different volunteers. A range of morphological characteristics i.e., distribution of pigmentation, root shape, cuticle thickness, and cuticle scale pattern, medullary patterns, shaft diameter, texture, and certain other microscopic features, were investigated across genders. The presence and edge characteristics of ovoid (oval) bodies were also noted as ancillary microscopic features. The empirical observations of the present study, when considered alongside findings reported in previous literature, indicate certain gender-associated trends in hair morphology.
Heredity plays a significant role in determining hair characteristics, despite considerable overlap in microscopic features between male and female scalp hair.. A greater average hair shaft diameter was observed in male hair (98.2 ± 12.42 μm) compared to female hair (73.88 ± 10.84 μm). Male hair samples generally exhibited a smoother surface appearance and comparatively thicker cuticular layers under light microscopy. . Similarly, other parameters like number of split ends, a wider natural color range were also observed. The key observation of this study was the presence of discernible gender-related trends in selected microscopic features of male and female scalp hair.
Keywords
forensic sciences, human hair, light microscopy, morphological characteristics, gender determination, microscopic hair examination
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References
Puri, A. and N. Arya, Hair Analysis, in Fundamentals of Forensic Biology. 2024, Springer. p. 505-514.
Robertson, J., Managing the forensic examination of human hairs in contemporary forensic practice. AustrAliAn JournAl of forensic sciences, 2017. 49(3): p. 239-260.
Bisbing, R.E., The forensic identification and association of human hair. Forensic Science Handbook, Volume I, 2020: p. 151-200.
Funes, D.S., et al., Morphological and chemical profiling for forensic hair examination: A review of quantitative methods. Forensic Science International, 2023. 346: p. 111622.
Mussabekova, S.A. and X.E. Mkhitaryan, Elemental composition of hair as a marker for forensic human identification. Journal of Forensic and Legal Medicine, 2021. 81: p. 102182.
Popescu, C. and H. Höcker, Hair—the most sophisticated biological composite material. Chemical Society Reviews, 2007. 36(8): p. 1282-1291.
Araújo, R., et al., Biology of human hair: know your hair to control it. Biofunctionalization of Polymers and their Applications, 2011: p. 121-143.
Yukuyama, M.N., G.L.B. De Araújo, and N.A. Bou-Chacra, Nanomaterials for hair care applications. Nanocosmetics, 2020: p. 205-225.
Koch, S.L., et al., The biology of human hair: A multidisciplinary review. American Journal of Human Biology, 2020. 32(2): p. e23316.
Kataria, S., et al., Investigating the morphology and genetics of scalp and facial hair characteristics for phenotype prediction. Science & Justice, 2023. 63(1): p. 135-148.
Harshini, S.S., et al., Comparative study of male and female human hair: A microscopic analysis. Journal of Advanced Pharmaceutical Technology & Research, 2022. 13(Suppl 1): p. S297-S301.
Wilkinson, L. and C. Gwinnett, An international survey into the analysis and interpretation of microscopic hair evidence by forensic hair examiners. Forensic science international, 2020. 308: p. 110158.
Hashimoto, K., The structure of human hair. Clinics in dermatology, 1988. 6(4): p. 7-21.
Ogle Jr, R.R. and M.J. Fox, Atlas of human hair: Microscopic characteristics. 2017: Crc Press.
Wortmann, F.J., G. Wortmann, and T. Sripho, Why is hair curly?—Deductions from the structure and the biomechanics of the mature hair shaft. Experimental dermatology, 2020. 29(3): p. 366-372.
Koch, S.L., M.D. Shriver, and N.G. Jablonski, Variation in human hair ultrastructure among three biogeographic populations. Journal of structural biology, 2019. 205(1): p. 60-66.
Moeller, M., P. Fey, and H. Sachs, Hair analysis as evidence in forensic cases. Forensic science international, 1993. 63(1-3): p. 43-53.
Lasisi, T., et al., High-throughput phenotyping methods for quantifying hair fiber morphology. Scientific reports, 2021. 11(1): p. 11535.
Takahashi, T., Unique hair properties that emerge from combinations of multiple races. Cosmetics, 2019. 6(2): p. 36.
Hayashi, S., I. Miyamoto, and K. Takeda, Measurement of human hair growth by optical microscopy and image analysis. British journal of dermatology, 1991. 125(2): p. 123-129.
Deedrick, D.W. and S.L. Koch, Microscopy of hair part 1: a practical guide and manual for human hairs. Forensic science communications, 2004. 6(1).
Salih, A., Laser scanning confocal imaging of forensic samples and their 3D visualization, in Digital Forensics for the Health Sciences: Applications in Practice and Research. 2011, IGI Global. p. 13-28.
Pomeranz, M., et al., High‐resolution computational imaging of leaf hair patterning using polarized light microscopy. The Plant Journal, 2013. 73(4): p. 701-708.
De La Mettrie, R., et al., Shape variability and classification of human hair: a worldwide approach. Human biology, 2007. 79(3): p. 265-281.
Thompson, A., A.S. Wilson, and J. Ehleringer, Hair as a geochemical recorder: ancient to modern. 2014.
Kintz, P., Hair analysis in forensic toxicology. Wiley Interdisciplinary Reviews: Forensic Science, 2019. 1(1): p. e1196.
Sen, J., Human hair in personal identification and documenting drug and substance abuse. The Anthropologist, 2010. 12(1): p. 47-58.
Zafarina, Z. and S. Panneerchelvam, Analysis of hair samples using microscopical and molecular techniques to ascertain claims of rare animal species. The Malaysian journal of medical sciences: MJMS, 2009. 16(3): p. 35.
Lasisi, T., The genetic architecture and evolutionary function of human scalp hair morphology. 2021: The Pennsylvania State University.
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