Hair Analysis for Drugs and Forensic Studies

Analysis of hair can often serve as a lead to even more complicated disorders. For example, a study by Capel et al. [166] indicated significantly higher concentrations of cadmium in hair from dyslexic children than in a normal control group. These scientists suggest that cadmium analysis of hair may be used in early detection and that excessive cadmium may be involved in this type of learning disorder. 

Menkes syndrome is linked to a copper deficiency resulting in abnormal keratinization [167]. In this genetic disorder, the kinky hair symptomatic of this disease results from an unusually high mercaptan level of cysteine, wherein only about 50% of the cysteine is oxidized to disulfide bonds during keratinization. 

Typing or analysis consists of reaction and color development of the replicated DNA sequence. The main technique at this time involves reaction with eight different oligonucleotide probes followed by color development [183]. These probes distinguish six alleles (Al.l, A1.2, A1.3, A2, A3, A4) that define 21 genotypes with frequencies of 0.005 to 0.15 [181,183,185]. Because PCR analysis permits identification of degraded DNA, it can be used to analyze ancient samples of human or even nonhuman DNA. Even newer techniques are under development to permit quantitation and even faster and more convenient qualitative identification of DNA for forensic, archaeological, and clinical research [186,187]. 

Bolling, D. The Amino Acid Composition of Proteins and Foods. Thomas, Springfield, IL (1952). 

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