Epigenetic age signatures in bones.

Age prediction can help identify skeletal remains by limiting the search range for a missing person. Although age prediction methods based on odontology and anthropology are frequently used in the forensic field, DNA methylation is particularly promising age-predictive biomarker. In this study, we generated genome-wide DNA methylation profiles of bone samples from 32 identified skeletal remains with an age at death ranging from 31 to 96 years. Only 12 provided more than 800 K quality-filtered CpG methylation values using Illumina's Infinium MethylationEPIC BeadChip array. Methylation ages of the bone samples calculated using a recently developed skin & blood clock composed of 391 CpG sites were found to be very similar to their actual ages (MAD = 6.4 years). However, the low success rate in methylation profiling of bone DNA samples may prevent researchers from applying the array to this type of samples. Therefore, we selected a set of CpG sites that would enable age prediction based on only a few CpG sites in bone DNA samples. Nineteen age-associated CpG marker candidates were selected from 720 K quality-filtered CpG values of 21 male skeletal remain samples. Because age signatures for blood, such as markers on the ELOVL2, FHL2, KLF14 and TRIM59 genes, had showed strong age associations in 12 bone samples, we further tested the age association of the 5 well-known markers in a blood-based model and the 13 out of 19 CpG markers from the array of 21 bone samples with an independent set of 30 skeletal remain samples using SNaPshot multiplex based on single nucleotide primer extension. Four CpG sites on TMEM51, TRIM59, ELOVL2, and EPHA6 genes showed moderate or weak correlations between methylation and age, which suggests further investigation of these markers to predict the age of bones.

The identification of elephant ivory evidences of illegal trade with mitochondrial cytochrome b gene and hypervariable D-loop region.

DNA analysis of elephant ivory of illegal trade was handled in this work. The speciation and geographical origin of nine specimens of elephant ivory were requested by the police. Without national authorization, the suspect had purchased processed ivory seals from January to May, 2011 by Internet transactions from a site in a neighboring country. The DNA of decalcified ivory evidences was isolated with QIAGEN Micro Kit. The total 844-904 base pair sized sequences of mitochondrial cytochrome b and D-loop region could be acquired using direct sequencing analysis. They were compared with the sequences registered in GenBank. It was confirmed that most specimens were likely from African forest elephants (Loxodonta cyclotis), one from African savanna elephant (Loxodonta africana) and one from Asian elephant (Elephas maximus). Analysis of the mitochondrial hypervariable D-loop region sequence of elephants verified that one African savanna elephant might be from South Africa and one Asian elephant from Laos. Cytochrome b and D-loop region located in the mitochondrial DNA resulted in the successful determination of elephant DNA from nine processed ivory specimens.

Population genetics and mutational events at 6 Y-STRs in Korean population.

Haplotype frequencies for 6 Y-STRs (DYS522, DYS533, DYS549, DYS570, DYS576 and DYS643) were determined in 539 unrelated Korean males. A total of 375 haplotypes were observed with the overall haplotype diversity of 0.9967. In DYS570, we found new point-3 microvariant allele series, i.e., 18.3, 19.3 and 20.3. DNA sequence analysis showed that the full repeat sequences were [TTTC](n)ttc[TTTC](5). Duplicated DYS643 allele was found and discussed on its forensic impact on the Y-STR interpretation of male-male mixtures. In 140 confirmed father/son pairs, one mutation was found in DYS576 with the overall mutation rate of 1.10x10(-3)/locus/generation (95% CI 0.31-1.89x10(-3)).

Genetic polymorphisms of 16 Y chromosomal STR loci in Korean population.

Allele frequencies and haplotypes of 16 Y chromosomal STR loci included in the AmpFlSTR((R)) Yfilertrade mark system were obtained from a sample of 526 unrelated Korean male individuals. A total of 478 haplotypes were observed in the 526 individuals studied, of which 440 were unique. The overall haplotype diversity for the 16 Y-STR loci was 0.9996, and the discrimination capacity was 0.9087. We found 13 atypical alleles, including null, duplicated and microvariant alleles. Microvariants have been characterized by sequencing, 14.1 allele at DYS458 showing the flanking site mutation, 13.1 and 15.2 allele at DYS385a/b showing changes in the repeat structure.

Sesquiterpenoids isolated from the flower buds of Tussilago farfara L. inhibit diacylglycerol acyltransferase.

Inhibition of acyl CoA:diacylglycerol acyltransferase (DGAT), which is a key enzyme in triglyceride synthesis in eukaryotic organisms, has been proposed as one of the drug targets for treating obesity, type II diabetes mellitus, and metabolic syndrome. Bioassay-guided fractionation of EtOH extract of the flower buds of Tussilago farfara , using an in vitro DGAT enzyme assay, resulted in the isolation of four known sesquiterpenoids, tussilagonone (1), tussilagone (2), 7beta-(3-ethyl-cis-crotonoyloxy)-1alpha-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (3), and 8-angeloylxy-3,4-epoxy-bisabola-7(14),10-dien-2-one (4). DGAT1 inhibitory activity was studied by in vitro DGAT assay using rat liver microsomes and HepG2 cell microsomes. They showed DGAT1 inhibition with IC(50) values of 99.2 (1), 18.8 (2), 47.0 (3), and 211.1 (4) microM (for rat liver microsomes) and >1 mM (1), 49.1 (2), 160.7 (3), and 294.4 (4) microM (for HepG2 cell microsomes), respectively. Compound 2 showed the most potent inhibition against microsomal DGAT1 derived from rat liver and human hepatocellular carcinoma HepG2 cells and also significantly inhibited triglyceride synthesis by suppressing incorporation of [(14)C]acetate or [(14)C]glycerol into triglycerides in HepG2 cells. These findings suggest that tussilagone is a potential lead compound in the treatment of obesity and type 2 diabetes.