Alu insertions, INDELs, and SNPs in the X chromosome can be useful not only for revealing relationships among populations but also for identification purposes. We present data of 10 Alu insertions, 5 INDELs, and 15 SNPs of X-chromosome from three Argentinian north-east cities in order to gain insight into the genetic diversity of the X chromosome within this region of the country. Data from 198 unrelated individuals belonging to Posadas, Corrientes, and Eldorado cities were genotyped for Ya5DP62, Yb8DP49, Ya5DP3, Ya5NBC37, Ya5DP77, Ya5NBC491, Ya5DP4, Ya5DP13, Yb8NBC634, and Yb8NBC102 Alu insertions, for MID193, MID1705, MID3754, MID3756 and MID1540 Indels and for rs6639398, rs5986751, rs5964206, rs9781645, rs2209420, rs1299087, rs318173, rs933315, rs1991961, rs4825889, rs1781116, rs1937193, rs1781104, rs149910, and rs652 SNPs. No deviations from Hardy-Weinberg equilibrium were observed for Posadas and Corrientes. However, Eldorado showed significant values, and it was found to have an internal substructuring with two groups of different origin, one showing higher similarity with European countries, and the other with more similarities to Posadas and Corrientes. Fst pairwise genetic distances emerged for some markers among the studied populations and also between our data and those from other countries and continents. Of particular interest, Alu insertions demonstrated the most differences, and could be of use in ancestry studies for these populations, while INDELs and SNPs variation were informative for differentiation within the country.

Eye color prediction based on an individual's genetic information is of interest in the field of forensic genetics. In recent years, researchers have studied different genes and markers associated with this externally visible characteristic and have developed methods for its prediction. The IrisPlex represents a validated tool for homogeneous populations, though its applicability in populations of mixed ancestry is limited, mainly regarding the prediction of intermediate eye colors. With the aim of validating the applicability of this system in an admixed population from Argentina (n = 302), we analyzed the six single nucleotide variants used in that multiplex for eye color and four additional SNPs, and evaluated its prediction ability. We also performed a genotype-phenotype association analysis. This system proved to be useful when dealing with the extreme ends of the eye color spectrum (blue and brown) but presented difficulties in determining the intermediate phenotypes (green), which were found in a large proportion of our population. We concluded that these genetic tools should be used with caution in admixed populations and that more studies are required in order to improve the prediction of intermediate phenotypes.

In northeast Argentina, different Amerindian communities share territory and history with settlers, mainly Europeans. Due to miscegenation, the current Argentinian population has a particular structure that can be described through the X chromosome variation. Our objectives are: to describe the variation of 10 X-STRs in urban populations of the Argentinian regions known as Gran Chaco and Mesopotamia; to report the forensic parameters of these STRs, and to estimate the European and indigenous genetic components in these regions. Population and forensic parameters were estimated for 419 individuals from the analysed populations, including two indigenous groups, Wichí and Mocoví, previously reported. Population structure was estimated through Fst and Rst distances and AMOVA calculations. The indigenous American and European components were assessed with STRUCTURE. X-STRs showed a high level of genetic variability in urban and indigenous populations. Indigenous people of the Gran Chaco region showed significant differentiation from the urban samples (Fst 5.5%) and also among themselves (Fst 5.3%). The genetic differentiation among urban groups is almost negligible instead population from Misión Nueva Pompeya differed from the rest of the city populations. Forensic parameters indicate that these X-STRs are useful as a complement to paternity tests. The set of 10 STRs could be a good tool for population differences.

Six new crotofolane diterpenoids ( 1 – 6 ) and 13 known compounds ( 7 – 19 ) were isolated from the MeOH–CH 2 Cl 2 (1:1, v/v) extracts of the leaves and stem bark of Croton kilwae . The structures of the new compounds were elucidated by extensive analysis of spectroscopic and mass spectrometric data. The structure of crotokilwaepoxide A ( 1 ) was confirmed by single-crystal X-ray diffraction, allowing for the determination of its absolute configuration. The crude extracts and the isolated compounds were investigated for antiviral activity against respiratory syncytial virus (RSV) and human rhinovirus type-2 (HRV-2) in HEp-2 and HeLa cells, respectively, for antibacterial activity against the Gram-positive Bacillus subtilis and the Gram-negative Escherichia coli , and for antimalarial activity against the Plasmodium falciparum Dd2 strain. ent -3β,19-Dihydroxykaur-16-ene ( 7 ) and ayanin ( 16 ) displayed anti-RSV activities with IC 50 values of 10.2 and 6.1 μM, respectively, while exhibiting only modest cytotoxic effects on HEp-2 cells that resulted in selectivity indices of 4.9 and 16.4. Compounds 2 and 5 exhibited modest anti-HRV-2 activity (IC 50 of 44.6 μM for both compounds), while compound 16 inhibited HRV-2 with an IC 50 value of 1.8 μM. Compounds 1 – 3 showed promising antiplasmodial activities (80–100% inhibition) at a 50 μM concentration.