Hair Analysis

Forensics / DNA

Hair analysis ;

A critical evaluation ?


At the scene of crime hair and fibre samples are collected from the surrounding area which can be used for the purposes of eliminating individuals from police enquiries as well as to help narrow down the list of suspects or victims.

Hair is one of the most telling pieces of trace evidence that can be collected from a crime scene and can provide strong corroborative evidence for placing an individual at a crime scene. The significance of a hair match is influenced by how often the examiner has matched certain hair characteristics.

There are standard procedure’s for search and rescue evidence gathering and although they probably do apply to Portugal as well as many other countries, they certainly do apply to UK forces who just happened to be in Portugal assisting the PJ following Madeleine’s disappearance, specialists in this area of policing, missing persons and investigative work were brought in, including Scotland Yard.

These procedures include capturing physical evidence which might assist in the identification and recovery of bodies or future enquiries into homicide. This means obtaining identifying characteristics for reference from objects left behind. Investigative effort must be made and recorded to establish as far as possible the link between the recovery and the missing person, hair being one of the biological samples collected.

Human hair is the subject of a wide range of scientific investigations. The chemical and physical properties of hair are of great importance to forensic scientists. Chemicals a person may have consumed can be detected and No two people will have the exact same chemicals in their hair, nor is it likely they would have the exact same hair characteristics.

Hair also contains trace quantities of metals like Gold, Sodium and Copper, which can be quantified by a process called Neutron Activation Analysis. The combination and quantity of these metals are unique in every individual to within a probability of one out of a million. Though it appears NAA was not used or considered in this case.

In all hair analysis there should be a correlation of microscopic and mitochondrial DNA hair comparisons.

Microscopic hair identification processes involves the examination and comparison of hair characteristics along the entire length of the hair(s). ie Longer hairs have more characteristics to compare, and the greater the variation along the length, the greater the degree of significance - color / pigmentation in the cortex, the cuticle pattern, texture, width race / ethnicity , lifestyles, Age and environment are just some of the factors which make everyone’s hair unique.

The basic morphology of human hairs is shared by every individual in the population, but the arrangement, distribution, and appearance of individual microscopic characteristics within different regions of hair allow a skilled hair examiner to differentiate hairs between individuals.

Although hair comparisons are not a basis for absolute personal identification it is very unusual to find hairs from two different individuals that exhibit the same characteristics.

A nuclear DNA match of the 15 core STR loci permits little doubt that a questioned sample has come from a known individual, except in the case of identical twins. However, because mitochondrial DNA ( mtDNA) is maternally inherited, all a woman’s offspring, her siblings, her mother, and other maternal relatives will have the same mitochondrial DNA profile .

** Mitochondrial DNA is not a unique identifier and in test conclusions it is important that a mitochondrial DNA analyst state clearly, both in a final report and in testimony, that an individual and his or her maternal relatives cannot be excluded as the donor of a questioned hair. -

ie- “meaning those samples were from that person or individuals of the same maternal bloodline. "

The question is, have they specifically excluded the people who's reference samples matched the hairs found ?

Does stating the samples are identical , mean those samples were from those persons or individuals of the same maternal bloodlines and does that exclude the person who’s reference sample matches the sample found ?

Two examples from the report that indicate that suspected crime scene hairs and reference hairs were not only identical, but were also not excluded.

ie - “ The Haplotype identified by the letters C e C*, present in 53 samples, and identical to that of Kate Healy (KH), mother of the victim and to that of Jose Maria Batista Roque (JMBR), meaning those sample were from those persons or individuals of the same maternal bloodlines. “

ie - " The Haplotype identified by the letter S, present in 2 samples, (apartment in Burgau), and identical to that of Jane Michelle Tanner (JT), meaning those samples were from that person or individuals of the same maternal bloodline. “

** “ in test’s conclusion it is important that a mitochondrial DNA analyst state clearly, both in a final report and in testimony, that an individual and his or her maternal relatives cannot be excluded as the donor of a questioned hair. “

Hairs can be transferred during physical contact, their presence can associate a suspect to a victim or a suspect / victim to a crime scene. The types of hair recovered and the condition and number of hairs found all impact on their value as evidence in a criminal investigation.

It’s understandable why there was a need for the analysis to check the National DNA Database and this no doubt would have been procedural as is recording any findings in the report.

However, by the same token this analysis was also done to compare trace evidence found in a location - i.e. samples of hair against known reference samples.

Like the Forensic Science Service’s Report of the DNA evidence, the results of the hair analysis have raised more questions than answers regarding the actual analysis and interpretation of the results.

It can only be described as bewildering that in over 400 samples of hair collected in this case, 53 belonging to Kate McCann or someone maternally related, NONE were specifically identified as belonging to the one person who they were looking for.

What’s even more concerning is the fact that it appears according to the report that hairs found in the hired vehicle were compared to hairs which were not confirmed as belonging to Madeleine.


‘ a total number of twelve [12] hairs or hair fragments were recovered from the tops SJM/2, SJM/4 and SJM/5. All of these appeared to be hair and not down, being mainly blonde in colour. One of the hairs was brown and distinctly darker than the other hairs, suggesting at the least, that this was a hair from someone else. ‘


‘The remaining eleven hairs/fragments varied in length from 4 millimetres to 45 millimetres [~1/8" to ~1,3/4"]. I could not conclude that all hairs were from the same person. If they had been from Madeleine McCann, then they are not representative/typical/characteristic of a sample of her hair, given the length of that seen in photographs of her.’


‘Conclusion
In the objects recovered from the Scenic, there were around 15 blonde/fair hairs similar to the reference hairs from SJM2, 4 and 5. However, as it was not possible to do solid [definitive] or significant [forensically meaningful] tests, it is not possible for me to determine if, or not, these could have been from Madeleine McCann .’


None of the samples from the tops SMJ2 , 4 & 5 were identified as belonging to Madeleine - Yet it appears that they were used as substitute reference samples to compare against hairs found in the hire vehicle.

Reference objects
‘ I received [obtained] information from the pillow-case SJM/1, the tops SJM2, 4 and 5, and the hairbrush SJM/36 belonging to Madeleine McCann or used by her. The hair found on these objects was used in substitution of [in place of] reference samples of her hair, [which were] not considered to be authentic samples of her hair.’


A child’s hair has obvious characteristics which should make it easily identifiable as such. Reference samples from siblings and family were readily available for comparison and an mtDNA test would have definitely confirmed any hair samples were from children of that family.
Reference hair samples from the twins should have been taken for comparison and elimination purposes.

If a scientist can distinguish the difference in someone’s hair by simply using photographs in order to compare with questionable samples, then surely doing morphological comparisons (microscopic association or match) would identify the difference between those questionable samples and reference samples belonging to siblings. Once that was done an mtDNA test on one of the questionable hair samples would confirm whether or not those hairs belonged to another / different sibling – and as we know there were presumably only 3 children.

Most hairs would not degrade or be damaged enough not to be able do tests after such a short period of time. If they were so badly damaged the question has to be asked why or how this damage may have occurred.

It’s astounding that a hair sample which supposedly belonged to Madeleine was found and given to the psychic D. Krugal to use in order for him to try and locate her body, yet no other hairs could be found for forensic purposes.







Cont.