New multiplex PCR sets of commonly used short tandem repeat (STR) markers have been developed to produce PCR products that are reduced in size when compared to standard commercial STR kits. The reduction in size of these amplicons can facilitate the examination and analysis of degraded DNA evidence by improving amplification efficiency. This "miniSTR" approach will permit current forensic practitioners to use STR markers and instrumentation already present in their laboratories and to generate genotyping data that is directly comparable to reference samples and searchable through the FBI's Combined DNA Index System (CODIS) databases. This paper discusses the development of these new primer sets and presents some initial results in the analysis of degraded and aged DNA samples. A method for removal of problematic fluorescent dye artifacts is also described. Comparison studies in over 100 samples have verified that these miniSTR primers can provide fully concordant results to commercial STR kits and can provide improved signal from degraded DNA specimens. These miniplex sets should prove valuable in the analysis of samples where allele dropout and reduced sensitivity of larger STR alleles occurs.

/pdf/the-development-of-reduced-size-str-amplicons-as-tools-for-2henjyl34q.pdf

The development of reduced size STR amplicons as tools for analysis of degraded DNA.

If bone is considered as a composite of collagen (protein) and bioapatite (mineral), then three pathways of diagenesis are identified: (1) chemical deterioration of the organic phase; (2) chemical deterioration of the mineral phase; and (3) (micro) biological attack of the composite. The first of these three pathways is relatively unusual and will only occur in environments that are geochemically stable for bone mineral. However, because rates of biomolecular deterioration in the burial environment are slow, such bones would yield useful biomolecular information. In most environments, bones are not in thermodynamic equilibrium with the soil solution, and undergo chemical deterioration (path 2). Dissolution of the mineral exposes collagen to biodeterioration, and in most cases the initial phase of dissolution will be followed by microbial attack (path 3). Biological attack (3) also proceeds by initial demineralization; therefore paths 2 and 3 are functionally equivalent. However,in a bone that follows path 3 the damage is more localized than in path 2, and regions equivalent to path 1 may therefore exist outside these zones of destruction.

Other biomolecules, such as blood proteins, cellular lipids and DNA, exist within the physiological spaces within bone.For these biomolecules, death history may be particularly important for their survival.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/1475-4754.t01-1-00071

The survival of organic matter in bone: a review

The presence of hundreds of copies of mitochondrial DNA (mtDNA) in each human cell poses a challenge for the complete characterization of mtDNA genomes by conventional sequencing technologies. Here we describe digital sequencing of mtDNA genomes with the use of massively parallel sequencing-by-synthesis approaches. Although the mtDNA of human cells is considered to be homogeneous, we found widespread heterogeneity (heteroplasmy) in the mtDNA of normal human cells. Moreover, the frequency of heteroplasmic variants varied considerably between different tissues in the same individual. In addition to the variants identified in normal tissues, cancer cells harboured further homoplasmic and heteroplasmic mutations that could also be detected in patient plasma. These studies provide insights into the nature and variability of mtDNA sequences and have implications for mitochondrial processes during embryogenesis, cancer biomarker development and forensic analysis. In particular, they demonstrate that individual humans are characterized by a complex mixture of related mitochondrial genotypes rather than a single genotype.

/pdf/heteroplasmic-mitochondrial-dna-mutations-in-normal-and-1gf3bbf99w.pdf

Heteroplasmic mitochondrial DNA mutations in normal and tumour cells

Lung cancer is the most frequent malignant neoplasm in most countries, and the main cancer-related cause of mortality worldwide in both sexes combined.The geographic and temporal patterns of lung cancer incidence, as well as lung cancer mortality, on a population level are chiefly determined by tobacco consumption, the main aetiological factor in lung carcinogenesis.Other factors such as genetic susceptibility, poor diet, occupational exposures and air pollution may act independently or in concert with tobacco smoking in shaping the descriptive epidemiology of lung cancer. Moreover, novel approaches in the classification of lung cancer based on molecular techniques have started to bring new insights to its aetiology, in particular among nonsmokers. Despite the success in delineation of tobacco smoking as the major risk factor for lung cancer, this highly preventable disease remains among the most common and most lethal cancers globally.Future preventive efforts and research need to focus on non-cigarette tobacco smoking products, as well as better understanding of risk factors underlying lung carcinogenesis in never-smokers.

https://erj.ersjournals.com/content/erj/48/3/889.full.pdf

Risk factors for lung cancer worldwide

The color of hair, skin, and eyes in animals mainly depends on the quantity, quality, and distribution of the pigment melanin, which occurs in two types: black to brown eumelanin and yellow to reddish pheomelanin. Microanalytical methods to quantify the amounts of eumelanin and pheomelanin in biological materials were developed in 1985. The methods are based on the chemical degradation of eumelanin to pyrrole-2,3,5-tricarboxylic acid and of pheomelanin to aminohydroxyphenylalanine isomers, which can be analyzed and quantitated by high performance liquid chromatography. This review summarizes and compares eumelanin and pheomelanin contents in various pigmented tissues obtained from humans, mice, and other animals. These methods have become valuable tools to study the functions of melanin, the control of melanogenesis, and the actions and interactions of pigmentation genes. The methods have also found applications in many clinical studies. High levels of pheomelanin are found only in yellow to red hairs of mammals and in red feathers of birds. It remains an intriguing question why lower vertebrates such as fishes do not synthesize pheomelanin. Detectable levels of pheomelanin are detected in human skin regardless of race, color, and skin type. However, eumelanin is always the major constituent of epidermal melanin, and the skin color appears to be determined by the quantity of melanin produced but not by the quality.

Quantitative Analysis of Eumelanin and Pheomelanin in Humans, Mice, and Other Animals: a Comparative Review

Classification system of frontal sinus patterns by radiography. Its application to identification of unknown skeletal remains.

https://projects.nfstc.org/workshops/resources/articles/The%20modified%20method%20of%20two-step%20differential.pdf

The modified method of two-step differential extraction of sperm and vaginal epithelial cell DNA from vaginal fluid mixed with semen

Microscopical study on estimation of time since death in skeletal remains.

The ultimate purpose of forensic hair comparison is to state whether a crime scene hair is of victim origin or of suspect origin. Many hair investigators have seriously devoted themselves to establishing individualizing characteristics, mainly based on morphological examinations. However, there has been a general consensus that it will never be possible to identify a hair definitely to a particular person, even in the case of hair samples showing peculiar morphology. The enhancement of the identification probalitity has been a main interest of many hair investigators. In a current situation of forensic hair comparison the accumulation of all available information for characterizing a hair is most desirable. Morphological examination should always be considered as the first step of forensic hair comparison. Analytical examinations can now be expected to give useful information due to the rapid progress of analytical instruments. Thus, a combination of morphological and analytical data can lead to the enhancement of identification probability. With this in mind, the progress of morphological examination as the traditional approach in the context of forensic hair examination is discussed. Then, the elemental analysis in the investigation of hair is reviewed. A new approach to forensic hair comparison is hair protein analysis. The current situation is described together with instrumental chemical analyses of hair, and the effective application of these techniques to forensic hair comparison is demonstrated. Moreover, the analysis of hair root isozymes is reviewed.

Forensic Hair Investigation

We describe new primers for the detection of the STR polymorphism at the CSF1PO locus. These primers have been designed to produce shorter amplicons (150–182 bp) than the primers in standard use (295–327 bp). The reliability of the new primers for CSF1PO typing has been demonstrated by testing on known samples and by sequence analysis. These primers are superior to the original primers with regard to electrophoretic resolution and utility for typing of severely degraded DNA.

Hajime Sato

Papers

Classification system of frontal sinus patterns by radiography. Its application to identification of unknown skeletal remains.

The modified method of two-step differential extraction of sperm and vaginal epithelial cell DNA from vaginal fluid mixed with semen

Microscopical study on estimation of time since death in skeletal remains.

Forensic Hair Investigation

Evaluation of new primers for CSF1PO