Selective quantification of human DNA by real-time PCR of FOXP2.

We established a simple quantitative PCR procedure with high specificity and sensitivity using TaqMan probes targeting the FOXP2 sequence. This assay distinguished human and nonhuman, including primates, samples with the exception of mouse, turtle, lizard, and fishes. However, the specific amplification of mouse, lizard, and turtle fragments of FOXP2 could be confirmed by electrophoresis after real-time PCR. Because the C(T) values obtained for human DNA were not affected by contaminating animal DNA at concentrations up to 30 times that of human DNA, we were able to estimate the concentration of human DNA in mixed specimens. This assay provides a reliable and useful method for routine quantification of human-specific DNA in forensic practice.

Kinship analysis using DNA typing from five skeletal remains with an unusual postmortem course.

The skeletal remains of five individuals with an unusual postmortem course were discovered in a house. According to the explanation of the putative bereaved family, the postmortem interval of the five remains was between five and 20 years. They also explained to the police that they and the dead family members believed that the dead can be resurrected, and they had kept the bodies indoors, so the bodies had followed an unusual postmortem course. The five dead were identified by kinship analysis using DNA typing. For DNA extraction, we used the DNA extraction method with ultrafiltration and a silica-based DNA extraction kit. As a result, complete amplification STR profiles were obtained from DNA from bone samples of all five skeletons and their identity was proven by kinship testing.

Vibrotactile perception at glabrous and nonglabrous skin of fingers: repeatability of measurements and changes induced by acute vibration exposure.

OBJECTIVES: We sought to determine the within-session and between-session repeatability of vibrotactile perception threshold (VPT) measurements and the response patterns in VPT induced by acute exposure to short-term vibration from grasping a vibrating handle, at both glabrous and nonglabrous skin of fingers. METHODS: Baseline VPT was recorded twice at glabrous and nonglabrous side of fingers in the right hand of eight healthy volunteers. Then, the subjects were exposed to three exposure conditions (vibration at 31.5 Hz and 250 Hz, and no vibration), from gripping a vertical handle by the right hand, conducted on 3 different days at an interval of 1-3 wk. After exposure, the subjects released the hand and further VPT measurements at each location were made. RESULTS: Compared to the nonglabrous side, VPT measurements at the glabrous side demonstrated better within-session and between-session repeatability with lower coefficient of repeatability and higher intraclass correlation coefficient. After exposure, a significant increase in VPT was noted under both 31.5 Hz and 250 Hz (p<0.05-0.001) exposure conditions in the glabrous finger. In the nonglabrous finger, a pronounced increase in VPT was revealed under 250 Hz exposure condition (p=0.05). CONCLUSIONS: While measuring VPT at glabrous and/or nonglabrous fingers, the importance of the site of measurement should be considered; the repeatability for such measurements appears to be better at the glabrous site. At high frequency, vibrotactile perception appears to be affected in both glabrous and nonglabrous skin from acute vibration exposure.

Simple and sensitive method for identification of human DNA by allele-specific polymerase chain reaction of FOXP2.

The forkhead box P2 (FOXP2) gene is specifically involved in speech and language development in humans. The sequence is well conserved among many vertebrate species but has accumulated amino acid changes in the human lineage. The aim of this study was to develop a simple method to discriminate between human and nonhuman vertebrate DNA in forensic specimens by amplification of a human-specific genomic region. In the present study, we designed an allele-specific polymerase chain reaction (PCR) using primers to amplify smaller than 70-bp regions of FOXP2 to identify DNA as being of human or nonhuman, including ape, origin. PCR amplification was also successfully performed using fluorescence-labeled primers, and this method allows a single PCR reaction with a genomic DNA sample as small as 0.01 ng. This system also identified the presence of human DNA in two blood stains stored for 20 and 38 years. The results suggested the potential usefulness of FOXP2 as an identifier of human DNA in forensic samples.