Is Animal Hair Tapered At The End Of Shaft
Malays J Med Sci. 2009 Jul-Sep; 16(3): 35–twoscore.
Analysis of hair samples using microscopical and molecular techniques to ascertain claims of rare animal species
Received 2008 Sep x; Accustomed 2009 May 24.
Abstract
Background:
An unidentified beast species named the Jenglot and claimed to exist a rare living animal species was recently plant in the deep jungle of Irian Jaya, Republic of indonesia; brought to Kuala Lumpur, Malaysia by a man of affairs; and exhibited in a local museum. The possessor of the Jenglot carcasses had made a asking to perform DNA analysis on the Jenglot to ascertain its species.
Methods:
Because the muscle appeared very dry and recovery of Deoxyribonucleic acid was extremely difficult, nosotros therefore used the animals' hair for further assay. Hair samples were collected from three unlike Jenglots that were different in colour and concrete appearance. The samples were labelled as A, B, C and D, respectively.
Results:
Microscopic characteristics indicated that all 4 hair samples were of human origin, with a medullary index less than one/3 and pigment distribution towards the periphery. The scale pattern on the hair samples was of the imbricate blazon, adding certainty to the hypothesis of human origin. A dried root sheath was found in samples B and C, which was contrary to expectations since the sample collection method left a few cm of hair on the body of the Jenglots. Sample D had black dye granules over the cuticular surface. Sequencing of the mitochondrial DNA (mtDNA) hypervariable segment I (HVS-I) region showed polymorphisms at positions 16140, 16182C, 16183C, 16189, 16217 and 16274 and heteroplasmy at positions 16112, 16232 and 16251, a human-specific mtDNA haplotype that was consistent across all the samples.
Conclusions:
Based on these findings, it was ended that it is unlikely that the samples of Jenglot hair originated from an animal species.
Keywords: Hair, mitochondrial DNA, microscopial analysis, health sciences
Introduction
Morphological test of hair samples is the starting time step in forensic hair comparisons. The main medico-legal concerns with hair examination include identification of the species of origin, ascertainment of the hair's provenance from the torso and, finally, comparison of the control hair sample from the victim to the hair sample from the criminal offense scene. Though it is non possible to definitely identify a sample of pilus originating from a item person's head, unequivocal conclusion of human origin can exist established based on microscopic examination of the pilus'southward cuticle, cortex, medulla and pigment granules (1).
Human and animal hairs show similarities in having an outer cuticle, cortex and medulla. The outer surface of the hair is covered by scales. Though there are similar morphological features, the scale pattern provides distinguishing characteristics between animal and homo hairs. The scales of an animate being'south hair evidence many distinctions such as coronal (crown-like) and spinuous patterns, whereas in the case of humans the scale patterns are of the 'imbricate' type (flattened) (Effigy 1) (ii,3). Besides, the medullary index, which is the ratio of the medulla'due south width to the diameter of the hair, is ane/three and below in humans compared to greater than 1/three in animal hairs, due to the greater width of the medulla in animals (ii,3).
Representative diagram showing dissimilar scale patterns plant on hairs: a, an imbricate scale pattern is unique to human; b, spinuous; c, coronal patterns are observed on fauna hairs.
With the advocacy of forensic DNA typing, microscopic hair comparisons and DNA analysis can exist complementary and provide data on the source of a hair. In this case analysis, hair samples were obtained from three Jenglots, which were claimed to be a rare living creature species just found in the deep jungle of Irian Jaya, Indonesia. Iii Jenglots were bought from West Java by a Malaysian man of affairs for his personal collection and exhibited in one of the museums in Kuala Lumpur, where they have attracted numerous visitors. A request was and then fabricated past the possessor of the Jenglot carcasses to the authors to perform Deoxyribonucleic acid analysis then as to define the veracity of the claim that they are a rare creature species. Hair samples were collected from 3 different Jenglots and were labeled as A, B, C and D. Samples A and B were taken from a medium-size Jenglot carcass, which was 32 cm tall. Sample C was collected from a xvi.8-cm tall Jenglot while sample D was nerveless from the biggest Jenglot, which was 61.three cm tall. All pilus samples were nerveless from the head region of the Jenglots by cutting at the distal end of the hair.
Materials and Methods
Several strands of hair were placed in parallel on a microscope slide and two drops of water were added over the hairs in order to hold them in identify. A cover slip was placed over the hairs and they were scanned forth their length at 100x and 400x under a compound microscope to notice the morphological characteristics of the cuticle and medulla, and the distribution of pigment in the cortex. The medullary index and the bore of the hairs were calculated using an ocular micrometer calibrated with a stage micrometer at 100x and 400x (iv).
It is ofttimes very difficult to directly observe scale patterns from hair strands on a slide. Hence, a bandage was made using smash polish to obtain the impression of the scales. A thin layer of nail polish was spread on a microscope slide and a hair was placed in the center of the slide. It was allowed to correspond 15 minutes and so that the blast polish could harden and the hair was then gently removed using forceps (iv). The calibration pattern was observed under a compound microscope at 100x and 400x.
DNA was extracted from each hair sample using the Promega hair and tissue extraction kit and Promega Deoxyribonucleic acid IQ™ system (Promega, USA), following the manufacturer's protocols. Hair samples were thoroughly washed using lather solution and air-dried prior to the extraction to avert contagion. The hypervariable segment I (HVS-I) region of human mtDNA was amplified using 2 sets of human being-specific primers (L15996 and {"type":"entrez-nucleotide","attrs":{"text":"H16213","term_id":"881033","term_text":"H16213"}}H16213; L16128 and {"type":"entrez-nucleotide","attrs":{"text":"H16432","term_id":"881252","term_text":"H16432"}}H16432) (v) and sequenced. Polymorphisms were reported past aligning the HVS-I sequence from the pilus samples with the Cambridge Reference Sequence (half-dozen).
Results and Word
Hair is an outgrowth of the skin produced from a structure chosen the hair follicle and found merely in mammals. Humans develop hair follicles during foetal development and no new follicles are produced after birth. Hair is composed of the protein keratin and it is also the primary component of finger and toe nails (7).
Forensic analysis of hair centres on colour and construction, determined through microscopic magnification. The hair shaft has 3 forensically relevant layers: the cuticle, cortex and medulla. The cuticle has overlapping external scales, which helps in species identification. The scales of human hairs are imbricate whereas animal hairs show many singled-out patterns such as coronal (crown-similar) and spinuous scales (Effigy 1) (one,2,4).
Within the hair cuticle is the cortex, made up of spindle-shaped cells that contain the colour pigments; the way the pigments are distributed helps to identify hairs from particular individuals. Hair color is more often than not the effect of pigments and the pigments of human hairs are distinguishable from those of other mammals. Man hairs are generally consistent in colour and pigmentation throughout the length of the pilus shaft, whereas beast hairs may exhibit radical color changes over a short distance—a miracle known every bit banding (4). The distribution and density of pigments in human and animate being hairs can besides be identifiable features. The pigmentation of human being hairs is evenly distributed and denser toward the cuticle, whereas the pigmentation of animal hairs is more centrally distributed, i.due east., denser towards the medulla (1,ii,4,8,ix).
At the center of the hair shaft is the medulla, which is also valuable for species identification. Animals' medullary index (ratio of the medulla's diameter relative to the shaft'due south bore) is greater than humans'. Humans have a medullary index of less than 1/iii while the medullary index of animals is greater than ane/3. Nonetheless, the medulla is frequently fragmented or interrupted, which may consequence in differences in the identification of hairs from the same individual (1,2,4,8,9).
The results of the examination of the 4 hair samples labelled A, B, C and D are shown in Table 1. All hair samples were found to have a medullary alphabetize beneath 1/3, which is indicative of human origin (one,4,8,9). Moreover, moderate shaft diameter variations were observed in all four samples (Effigy 2) and the scale pattern was of the imbricate type, indicating homo origin (Figure iii) (one,iv,8,9). The pigments were distributed more towards the cuticular margin, which is also a characteristic indicative of man origin (Figure 4) (one,four,7–10).
Representative pilus from sample C (medullated) showing moderate shaft bore variation (100x).
Scale impression cast showing the imbricate nature of the scales of the Jenglot's hair (400x).
Medullated hair showing pigment granules more towards the cuticle (100x).
Table ane:
Results of morphological test of hair samples
| Characteristics examined | Sample A | Sample B | Sample C | Sample D |
|---|---|---|---|---|
| Color | Black and grayness hairs | Blackness and grey hairs | Brown and grey hairs | Nearly hairs were dark with blackish dye granules over the cuticular surface; very few without dye granules |
| Medulla | Medullated and non-medullated | Medullated and non-medullated | By and large non-medullated and a few with a medulla | Few hairs with a medulla - faintly visible |
| End morphology | Cut at ane end and with a tapered tip |
|
| Cut at one end and with a tapered tip |
| Shaft diameter | Coarse and usually with footling or no variation (80–110 μm) | Coarse and usually with little or no variation (80–120 μm) | Coarse and ordinarily with little or no variation (eighty–110 μm) | Coarse and usually with picayune or no variation (fourscore–120 μm) |
| Pigment distribution | Pigment was found to be more dense towards the periphery (cuticle) | Pigment was found to be more dense towards the periphery (cuticle) | Pigment was found to be more dense towards the periphery (cuticle) | Pigment was found to exist more than dense towards the periphery (cuticle) |
| Scales | Imbricate scales | Imbricate scales | Imbricate scales | Imbricate scales |
| Dye | - | - | - | Dye granules can exist seen over the cuticular surface and were besides found dissolved in acetone used to take scale impressions |
Blackness dye granules were conspicuously visible under microscopic examination of the clear nail varnish imprints of the pilus, indicating dyeing of the hairs in sample D (Effigy 5). A few hairs from samples B and C as well had an intact dried root at the other end of the cut tip, which indicated that the hairs were implanted upside down on the Jenglots' heads (Effigy 6).
Black dye granules found when mounting a hair from sample D for calibration casting in nail smoothen (100x).
A pilus from sample B with a dried-up hair root that appeared at the other end from the cutting tip, which indicated that the hair was implanted upside downwardly on the Jenglot's head (100x).
The mtDNA HVS-I region was successfully amplified using human-specific primers, supporting the morphological findings indicating the human origin of these hairs. Sequence assay of the HVS-I fragment showed polymorphisms at positions 16140, 16182C, 16183C, 16189, 16217 and 16274 and heteroplasmy at positions 16112, 16232 and 16251. This haplotype was consistent across all the samples, suggesting a maternal relationship between the owners of the hairs or that all the pilus samples might take originated from the same private.
Conclusion
Classical morphological analysis of hair samples, jointly with mtDNA sequence-based analysis, was useful in disproving the claim of a rare brute species in this instance. The morphological characteristics observed and the mtDNA sequence analysis proved that the pilus samples are of homo origin and had been implanted on the Jenglot carcasses' heads. This certainly disproves the merits and myth that the Jenglot is a rare animal species.
Acknowledgments
The authors wish to give thanks the Dean of the School of Wellness Sciences, Universiti Sains Malaysia, for assuasive the states to deport out this written report using the schoolhouse facilities.
Footnotes
Author'due south contributions
Conception and design, last approval of the article: ZZ Information collection, associates, analysis and interpretation; drafting of the article: SP, ZZ
References
1. Gaudette BD. A supplementary give-and-take of probabilities and human pilus comparisons. J Forensic Sci. 1982;27:279–289. [PubMed] [Google Scholar]
4. Robertson J. Forensic Examination of Pilus. Taylor and Francis; London: 1999. Forensic and microscopic examination of human pilus; pp. 79–154. [Google Scholar]
v. Lutz Due south, Weisser HJ, Heizmann J, Pollak S. Location and frequency of polymorphic positions in the mtDNA control region of individuals from Germany. Int J Legal Med. 1998;111:67–77. [PubMed] [Google Scholar]
six. Andrews RM, Kubacka I, Chinnery PF, Lightowlers RN, Turnbull DM, Howell Due north. Reanalysis and revision of the Cambridge reference sequence for human mitochondrial DNA. Nat Genet. 1999;23:147. [PubMed] [Google Scholar]
7. Montagna Westward, Vanscott EJ. The biological science of hair growth. In: Montagna W, Ellis RA, editors. New York: Academic Press Inc; 1958. pp. 39–64. [Google Scholar]
eight. Saferstein R. Criminalistics: An Introduction to Forensic Science. New Jersey: Prentice-Hall Inc; 1977. pp. 133–141. [Google Scholar]
nine. Deadman HA. Proceedings of the International Symposium on Forensic Pilus Comparisons; Federal Agency of Investigation. U.S. Government Printing Office; Washington DC: 1985. Homo hair comparing based on microscopic characteristics; pp. 45–50. [Google Scholar]
10. Kirk PL. Criminal offence Investigation, Physical Testify and The Police Laboratory. New York: Interscience Publishers Inc; 1953. pp. 152–175. [Google Scholar]
Articles from The Malaysian Journal of Medical Sciences : MJMS are provided hither courtesy of School of Medical Sciences, Universiti Sains Malaysia
Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3329137/
Posted by: wellshasurseen.blogspot.com
0 Response to "Is Animal Hair Tapered At The End Of Shaft"
Post a Comment