Development of multiplex assay with 16 SNPs on X chromosome for degraded samples.

We selected 16 new X chromosomal SNPs (rs4827155, rs471205, rs7884160, rs16982419, rs985251, rs3813932, rs6630351, rs4132871, rs5966270, rs7471388, rs6641116, rs6521038, rs5990560, rs5959408, rs414960, and rs3006142) and developed the two X chromosomal SNPs Octaplex systems using multiplex single base extension reactions. To make the systems more useful for analyzing degraded DNA samples, we designed primers to render amplicons of 100 bp or shorter (shorter PCR products). Statistical analyses of the 16 SNPs indicated a high usefulness for the Japanese forensic practice.

Unusual body posture after death leading to signs of strangulation.

This report concerns a case in which the decedent was found in a highly unusual posture, one resembling a yoga backbend pose. Several findings in this case pointed to death by strangulation, including facial congestion, extensive petechiae of the conjunctivae and mucosal membranes of the oral cavity, and congestion and hemorrhaging in the lingual root, laryngopharynx, and cervical lymph nodes. However, no hemorrhaging of the cervical skin or soft tissue was observed.

Evaluation of a new experimental kit for the extraction of DNA from bones and teeth using a non-powder method.

An experimental DNA extraction kit (new kit) was recently developed to extract DNA from degraded skeletal remains without the need for powdering the samples. We compared the utility of the new kit with the conventional phenol/chloroform method using real-time quantitative PCR and multiplex STR analysis. The new kit yielded large amounts of DNA from a compact bone fragment compared with the conventional phenol/chloroform method.

Restriction enzyme analysis of PCR products.

Progress in single nucleotide polymorphism (SNP) detection technologies has provided information for SNP-based studies, such as identification of candidate genes for the complex genetic diseases, pharmacogenetic analysis, drug development, population genetics, evolutionary studies, and forensic investigations. SNP detection is performed by many methods, including hybridization, allele-specific polymerase chain reaction (PCR), primer extension, oligonucleotide ligation, direct DNA sequencing, and endonuclease cleavage. Each of these methods has its specific advantages and disadvantages.