An optimal skeletal element for DNA testing: Evaluation of DNA quantity and quality from various bone types in routine forensic practice.

For human identification, the quality and quantity of DNA must be sufficient for amplification and analysis. When DNA extraction from bone tissues and teeth is required, the optimal skeletal elements should be selected as samples for DNA extraction because DNA yield differs among elements. Recently, some studies have reported that a high quantity of high-quality DNA can be extracted from the small cancellous bones of the hands and feet. In this study, we evaluated the effectiveness of small cancellous bones in the human identification of skeletal remains in routine forensic genetic casework. Cancellous bones [phalanges, (meta)carpal bones, and (meta)tarsal bones)] and the cortical bones (femur and petrous bones) and teeth, which have generally been recommended as samples, were collected from the same individuals that needed identifying using DNA analysis in our laboratory. The quantity of DNA from small cancellous bones tended to be higher than that from cortical bones, and the quality from the former was as high as that from the latter. This study showed that in routine forensic casework, the small cancellous bones of the hands and feet should be actively selected as samples for DNA testing.

Diversity of complement factor B/C2 in the common carp (Cyprinus carpio): three isotypes of B/C2-A expressed in different tissues.

Complement factor B and C2 are two critical proteases for complement activation. Some bony fish have been reported to possess duplicated genes for B/C2, but there is no direct evidence regarding possible functional divergence. Here, we report the isolation of the second and third isotypes of carp B/C2-A, a close relative of other bony fish B reported to date, and designated B/C2-A2 and B/C2-A3. B/C2-A1 (previously reported B/C2-A) and B/C2-A2 share 78% amino acid identity and are synthesized mainly in hepatopancreas. On the other hand, B/C2-A3 showed less (approximately 60%) sequence identity with the other two isotypes. It was expressed mainly in kidney and spleen, and was up-regulated after injection of carp with scleroglucan or sodium alginate, known immunostimulants for fish. Phylogenetic analysis suggests that B/C2-A3 diverged before separation of carp and zebrafish. B/C2-A3 represent a novel B/C2-lineage functioning as an acute phase reactant in cyprinid fish.