Development of an Okinawa panel for biogeographic inference of Okinawans.

BACKGROUND: The Precision ID Ancestry Panel with 165 SNP markers was unable to differentiate between mainland Japanese and Okinawa Japanese or to distinguish either of them from other East Asian populations. AIM: An Okinawa panel was developed with the aim of further separating Okinawa Japanese individuals from mainland Japanese and other Asian groups. Seventy-five SNPs were selected using the most informative markers from the literature. Further, 22 SNPs were selected to separate Okinawa Japanese at minimum SNPs. SUBJECTS AND METHODS: Samples were collected from 48 unrelated individuals from mainland Japan and 46 unrelated residents of the Okinawa prefecture. Data were evaluated by STRUCTURE, principal component, and GenoGeographer analyses. RESULTS: The 22 SNP set had similar levels of differentiation in STRUCTURE and PCA analyses as the 75 SNP set. GenoGeographer analysis showed that, out of the 46 Okinawa Japanese individuals, the 75 SNP and 22 SNP sets correctly assigned the Okinawan population as the most likely population of origin for 32 and 31 individuals, respectively. CONCLUSION: Neither SNP set could completely differentiate between Okinawa Japanese and other Asian groups, however, these sets should be useful for crime investigation, when the sample, cost and time are limited.

Montreal Cognitive Assessment (MoCA): A validation study among prisoners.

BACKGROUND: There are numerous scales for screening cognitive performance and thus identification of any potential deficits, but in spite of the vulnerability of the prison population to such problems, there has been no adequate validation of screening tools specifically for use with prisoners or others in the criminal justice system. AIM: To validate the Montreal Cognitive Assessment (MoCA) for use with prisoners. METHODS: 100 adult prisoners in one Portuguese prison were randomly invited by clinicians to take part in this study. A same size sample of community-living adult non-offenders of similar age was selected from the MoCA's normative study database in Portugal. For both groups, the key inclusion criterion was fluency in the Portuguese language. All participants completed the Mini Mental State Examination (MMSE) and the MoCA, both in Portuguese translation. Cronbach's alpha coefficient was calculated as an index of internal consistency and Pearson's r correlations calculated. Group performances were compared using independent samples t-test. Covariance analysis (ANCOVA) was computed with level of education as covariate. To measure the magnitude of the effect, η p 2 ${\eta }_{p}^{2}$ was used. A receiver operating characteristics curve analysis was computed to evaluate the discriminatory accuracy of MoCA and MMSE. RESULTS: The MoCA showed a 'reasonable' internal consistency index (α = 0.75) as well as positive and significant correlations with the MMSE. As a cognitive measure, however, the MoCA showed consistently superior psychometric properties and higher discriminatory accuracy (MoCA = 89%) than the MMSE (65%). According to the Youden index, the optimal cut-off point for the MoCA is below 24 points, whereas for the MMSE, it is below 27. CONCLUSIONS: The MoCA is a valid cognitive screening tool for use with prisoners. Further validations against detailed cognitive evaluation would be a useful next step.

Genetic analysis of sixteen autosomal STR loci in three Tunisian populations from Makthar, Nabeul and Sousse.

BACKGROUND: Due to its strategic location, Tunisia witnessed the succession and influence of many civilisations throughout history. However, the majority of studies carried out on Tunisia are focussed on Barbarian ethnicity. AIM: To estimate genetic diversity and genetic structure of three Tunisian populations using autosomal STRs. SUBJECTS AND METHODS: 278 individuals were analysed for sixteen STRs. Allele frequencies and statistical parameters were determined. RESULTS: The studied populations showed genetic affinity with geographically close populations. AMOVA showed no genetic difference between the Tunisian populations. Nevertheless, the variance between the populations of the same group was significant, reflecting their heterogeneity even though they came from the same geographical area, and had the same ethnicity and complex demographic history. CONCLUSION: Our results strongly supported the application of autosomal genetic markers in anthropological and forensic studies. The analyses conducted at the 15-loci level provide the resolution to assess the phylogenetic relationships among the populations examined and other geographically targeted worldwide populations, while the results resulting from the 10-loci studies provide an understanding of the relationships and origins of the North African populations. Furthermore, the current report demonstrates that the battery of autosomal STRs reported are useful, providing the power of discrimination for forensic and paternity analyses.

Skin pigmentation and genetic variants in an admixed Brazilian population of primarily European ancestry.

Although many genes have been shown to be associated with human pigmentary traits and forensic prediction assays exist (e.g. HIrisPlex-S), the genetic knowledge about skin colour remains incomplete. The highly admixed Brazilian population is an interesting study population for investigation of the complex genotype-phenotype architecture of human skin colour because of its large variation. Here, we compared variants in 22 pigmentary genes with quantitative skin pigmentation levels on the buttock, arm, and forehead areas of 266 genetically admixed Brazilian individuals. The genetic ancestry of each individual was estimated by typing 46 AIM-InDels. The mean proportion of genetic ancestry was 68.8% European, 20.8% Sub-Saharan African, and 10.4% Native American. A high correlation (adjusted R2 = 0.65, p < 0.05) was observed between nine SNPs and quantitative skin pigmentation using multiple linear regression analysis. The correlations were notably smaller between skin pigmentation and biogeographic ancestry (adjusted R2 = 0.45, p < 0.05), or markers in the leading forensic skin colour prediction system, the HIrisPlex-S (adjusted R2 = 0.54, p < 0.05). Four of the nine SNPs, OCA2 rs1448484 (rank 2), APBA2 rs4424881 (rank 4), MFSD12 rs10424065 (rank 8), and TYRP1 1408799 (rank 9) were not investigated as part of the HIrisPlex-S selection process, and therefore not included in the HIrisPlex-S model. Our results indicate that these SNPs account for a substantial part of the skin colour variation in individuals of admixed ancestry. Hence, we suggest that these SNPs are considered when developing future skin colour prediction models.

Sequencing of mitochondrial genomes using the Precision ID mtDNA Whole Genome Panel.

Massively parallel sequencing offers a fast and cost-effective method for sequencing of the whole mtDNA genome. The Precision ID mtDNA Whole Genome Panel amplifies the entire mtDNA genome in two multiplex PCRs with 81 primer sets using the Ion AmpliSeq™ technology. In this study, the performance of the panel was evaluated by testing different amplification methods (two-in-one or conservative), the number of PCR cycles (21, 23, and 25), and different reaction volumes (recommended volume or half-volume). Furthermore, a dilution series, controlled mtDNA mixtures, and casework samples were also sequenced. The normalised read depths of the individual fragments were highly consistent irrespectively of the amplification methods or reaction volumes used. The sequencing output matched the mixture ratios of the controlled mtDNA mixtures indicating that the sequencing results were a loyal representation of the input DNA. Complete mtDNA profiles were generated from <10 pg genomic DNA. Seven fragments with relatively low read depths and large variations in read depth were identified. One of these fragments covered part of the control region and the hypervariable region II.

Oral Health of Portuguese Children with Type 1 Diabetes: A Multiparametric Evaluation.

OBJECTIVE: To perform a multiparametric evaluation of the oral health of 36 children with type 1 diabetes. STUDY DESIGN: A group of type 1 diabetic children and a sex-age-matched control group were formed. Seven parameters were evaluated: probing depth, bleeding on probing, plaque index (O'Laery index), calculus index (according to Ramfjord), dental caries (using ICDAS), salivary pH and unstimulated salivary flow rate. Statistical analysis was performed and the significance level was set at 5%. RESULTS: Both groups consisted of 36 children with a mean age of 13 years. With regard to bleeding on probing, plaque index and calculus index, higher values were obtained in the diabetic group and the differences between groups were statistically significant for all three parameters. Concerning dental caries and salivary parameters, there were no significant differences between groups. However, a statistically significant correlation between salivary parameters and metabolic control was found. CONCLUSION: This study suggests that type 1 diabetic children are associated with some risk factors related to periodontal disease and dental caries. The proven relationship between diabetes and oral health complications imposes the need for these patients to be integrated into preventive dental programs from a young age.

A study of the peopling of Greenland using next generation sequencing of complete mitochondrial genomes.

OBJECTIVES: The Greenlandic population history is characterized by a number of migrations of people of various ethnicities. In this work, the analysis of the complete mtDNA genome aimed to contribute to the ongoing debate on the origin of current Greenlanders and, at the same time, to address the migration patterns in the Greenlandic population from a female inheritance demographic perspective. METHODS: We investigated the maternal genetic variation in the Greenlandic population by sequencing the whole mtDNA genome in 127 Greenlandic individuals using the Illumina MiSeq® platform. RESULTS: All Greenlandic individuals belonged to the Inuit mtDNA lineages A2a, A2b1, and D4b1a2a1. No European haplogroup was found. DISCUSSION: The mtDNA lineages seem to support the hypothesis that the Inuit in Greenland are descendants from the Thule migration. The results also reinforce the importance of isolation and genetic drift in shaping the genetic diversity in Greenlanders. Based on the mtDNA sequences, the Greenlandic Inuit are phylogenetically close to Siberian groups and Canadian Inuit.

Nitrite reductase activity of rat and human xanthine oxidase, xanthine dehydrogenase, and aldehyde oxidase: evaluation of their contribution to NO formation in vivo.

Nitrite is presently considered a NO "storage form" that can be made available, through its one-electron reduction, to maintain NO formation under hypoxia/anoxia. The molybdoenzymes xanthine oxidase/dehydrogenase (XO/XD) and aldehyde oxidase (AO) are two of the most promising mammalian nitrite reductases, and in this work, we characterized NO formation by rat and human XO/XD and AO. This is the first characterization of human enzymes, and our results support the employment of rat liver enzymes as suitable models of the human counterparts. A comprehensive kinetic characterization of the effect of pH on XO and AO-catalyzed nitrite reduction showed that the enzyme's specificity constant for nitrite increase 8-fold, while the Km(NO2(-)) decrease 6-fold, when the pH decreases from 7.4 to 6.3. These results demonstrate that the ability of XO/AO to trigger NO formation would be greatly enhanced under the acidic conditions characteristic of ischemia. The dioxygen inhibition was quantified, and the Ki(O2) values found (24.3-48.8 µM) suggest that in vivo NO formation would be fine-tuned by dioxygen availability. The potential in vivo relative physiological relevance of XO/XD/AO-dependent pathways of NO formation was evaluated using HepG2 and HMEC cell lines subjected to hypoxia. NO formation by the cells was found to be pH-, nitrite-, and dioxygen-dependent, and the relative contribution of XO/XD plus AO was found to be as high as 50%. Collectively, our results supported the possibility that XO/XD and AO can contribute to NO generation under hypoxia inside a living human cell. Furthermore, the molecular mechanism of XO/AO-catalyzed nitrite reduction was revised.

Mosaic maternal ancestry in the Great Lakes region of East Africa.

The Great Lakes lie within a region of East Africa with very high human genetic diversity, home of many ethno-linguistic groups usually assumed to be the product of a small number of major dispersals. However, our knowledge of these dispersals relies primarily on the inferences of historical, linguistics and oral traditions, with attempts to match up the archaeological evidence where possible. This is an obvious area to which archaeogenetics can contribute, yet Uganda, at the heart of these developments, has not been studied for mitochondrial DNA (mtDNA) variation. Here, we compare mtDNA lineages at this putative genetic crossroads across 409 representatives of the major language groups: Bantu speakers and Eastern and Western Nilotic speakers. We show that Uganda harbours one of the highest mtDNA diversities within and between linguistic groups, with the various groups significantly differentiated from each other. Despite an inferred linguistic origin in South Sudan, the data from the two Nilotic-speaking groups point to a much more complex history, involving not only possible dispersals from Sudan and the Horn but also large-scale assimilation of autochthonous lineages within East Africa and even Uganda itself. The Eastern Nilotic group also carries signals characteristic of West-Central Africa, primarily due to Bantu influence, whereas a much stronger signal in the Western Nilotic group suggests direct West-Central African ancestry. Bantu speakers share lineages with both Nilotic groups, and also harbour East African lineages not found in Western Nilotic speakers, likely due to assimilating indigenous populations since arriving in the region ~3000 years ago.

Performance of a 74-Microhaplotype Assay in Kinship Analyses.

Microhaplotypes (MHs) consisting of multiple SNPs and indels on short stretches of DNA are new and interesting loci for forensic genetic investigations. In this study, we analysed 74 previously defined MHs in two of the populations that our laboratory provides with forensic genetic services, Danes and Greenlanders. In addition to the 229 SNPs that originally made up the 74 MHs, 66 SNPs and 3 indels were identified in the two populations, and 45 of these variants were included in new definitions of the MHs, whereas 24 SNPs were considered rare and of little value for case work. The average effective number of alleles (Ae) was 3.2, 3.0, and 2.6 in Danes, West Greenlanders, and East Greenlanders, respectively. High levels of linkage disequilibrium were observed in East Greenlanders, which reflects the characteristics of this population that has a small size, and signs of admixture and substructure. Pairwise kinship simulations of full siblings, half-siblings, first cousins, and unrelated individuals were performed using allele frequencies from MHs, STRs and SNPs from Danish and Greenlandic populations. The MH panel outperformed the currently used STR and SNP marker sets and was able to differentiate siblings from unrelated individuals with a 0% false positive rate and a 1.1% false negative rate using an LR threshold of 10,000 in the Danish population. However, the panel was not able to differentiate half-siblings or first cousins from unrelated individuals. The results generated in this study will be used to implement MHs as investigative markers for relationship testing in our laboratory.

Microsatellites' mutation modeling through the analysis of the Y-chromosomal transmission: Results of a GHEP-ISFG collaborative study.

The Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) organized a collaborative study on mutations of Y-chromosomal short tandem repeats (Y-STRs). New data from 2225 father-son duos and data from 44 previously published reports, corresponding to 25,729 duos, were collected and analyzed. Marker-specific mutation rates were estimated for 33 Y-STRs. Although highly dependent on the analyzed marker, mutations compatible with the gain or loss of a single repeat were 23.2 times more likely than those involving a greater number of repeats. Longer alleles (relatively to the modal one) showed to be nearly twice more mutable than the shorter ones. Within the subset of longer alleles, the loss of repeats showed to be nearly twice more likely than the gain. Conversely, shorter alleles showed a symmetrical trend, with repeat gains being twofold more frequent than reductions. A positive correlation between the paternal age and the mutation rate was observed, strengthening previous findings. The results of a machine learning approach, via logistic regression analyses, allowed the establishment of algebraic formulas for estimating the probability of mutation depending on paternal age and allele length for DYS389I, DYS393 and DYS627. Algebraic formulas could also be established considering only the allele length as predictor for DYS19, DYS389I, DYS389II-I, DYS390, DYS391, DYS393, DYS437, DYS439, DYS449, DYS456, DYS458, DYS460, DYS481, DYS518, DYS533, DYS576, DYS626 and DYS627 loci. For the remaining Y-STRs, a lack of statistical significance was observed, probably as a consequence of the small effective size of the subsets available, a common difficulty in the modeling of rare events as is the case of mutations. The amount of data used in the different analyses varied widely, depending on how the data were reported in the publications analyzed. This shows a regrettable waste of produced data, due to inadequate communication of the results, supporting an urgent need of publication guidelines for mutation studies.

SNPtotree-Resolving the Phylogeny of SNPs on Non-Recombining DNA.

Genetic variants on non-recombining DNA and the hierarchical order in which they accumulate are commonly of interest. This variant hierarchy can be established and combined with information on the population and geographic origin of the individuals carrying the variants to find population structures and infer migration patterns. Further, individuals can be assigned to the characterized populations, which is relevant in forensic genetics, genetic genealogy, and epidemiologic studies. However, there is currently no straightforward method to obtain such a variant hierarchy. Here, we introduce the software SNPtotree v1.0, which uniquely determines the hierarchical order of variants on non-recombining DNA without error-prone manual sorting. The algorithm uses pairwise variant comparisons to infer their relationships and integrates the combined information into a phylogenetic tree. Variants that have contradictory pairwise relationships or ambiguous positions in the tree are removed by the software. When benchmarked using two human Y-chromosomal massively parallel sequencing datasets, SNPtotree outperforms traditional methods in the accuracy of phylogenetic trees for sequencing data with high amounts of missing information. The phylogenetic trees of variants created using SNPtotree can be used to establish and maintain publicly available phylogeny databases to further explore genetic epidemiology and genealogy, as well as population and forensic genetics.

Prediction of chronological age and its applications in forensic casework: methods, current practices, and future perspectives.

Estimating an individual's age can be relevant in several areas primarily related to the clinical and forensic fields. In the latter, estimation of an individual's chronological age from biological material left by the perpetrator at a crime scene may provide helpful information for police investigation. Estimation of age is also beneficial in immigration cases, where age can affect the person's protection status under the law, or in disaster victim identification to narrow the list of potential missing persons. In the last decade, research has focused on establishing new approaches for age prediction in the forensic field. From the first forensic age estimations based on morphological inspections of macroscopic changes in bone and teeth, the focus has shifted to molecular methods for age estimation. These methods allow the use of samples from human biological material that does not contain morphological age features and can, in theory, be investigated in traces containing only small amounts of biological material. Molecular methods involving DNA analyses are the primary choice and estimation of DNA methylation levels at specific sites in the genome is the most promising tool. This review aims to provide an overview of the status of forensic age prediction using molecular methods, with particular focus in DNA methylation. The frequent challenges that impact forensic age prediction model development will be addressed, together with the importance of validation efforts within the forensic community.

Pitfalls and challenges with population assignments of individuals from admixed populations: Applying Genogeographer on Brazilian individuals.

The assignment of individuals to a population can be of importance for the identification of mass disaster victims or criminal offenders in the field of forensic genetics. This assignment is based on biostatistical methods that process data of ancestry informative markers (AIMs), which are selected based on large allele frequency differences between the populations of interest. However, population assignments of individuals with an admixed genetic background are challenging. Admixed individuals are genetic mosaics of chromosomal segments from the parental populations, which may lead to ambiguous or no population assignment. This is problematic since admixture events are a substantial part of human history. In this study, we present challenges of interpreting the evidential weight of population assignments. We used Genogeographer for likelihood ratio (LR) calculations and Brazilians as examples of admixed individuals. Brazilians are a very heterogenous population representing a three-way admixture between Native Americans, Europeans, and Africans. Ancestry informative markers were typed in a total of 589 individuals from Brazil using the Precision ID Ancestry Panel. The Brazilians were assigned to six metapopulations (East Asia, Europe, Middle East, North Africa, South-Central Asia, Sub-Saharan Africa) defined in the Genogeographer software and LRs were calculated if the AIM profile was not an outlier in all metapopulations and simulated two-way (1:1) admixtures of the six metapopulations. Population assignments failed for 55% of the samples. These samples had significantly higher genetic contributions from East Asia, South-Central Asia and Sub-Saharan Africa, and significantly lower genetic contributions from Europe. Most of the individuals with population assignments were assigned to the metapopulations of Middle East (58%) or North Africa (36%), followed by Europe (4%), South-Central Asia (1%), and Sub-Saharan Africa (1%). For 8% of the samples, population assignments were only possible when assignments to simulated two-way (1:1) admixtures of the six metapopulations were considered. Most of these individuals were assigned to two-way admixtures of North Africa, South-Central Asia, or Sub-Saharan Africa. Relatively low median likelihood ratios (LRs<1000) were observed when comparing population likelihoods for Europe, Middle East, North Africa, South-Central Asia, or simulated 1:1 admixtures of these metapopulations. Comparisons including East Asian or Sub-Saharan African populations resulted in larger median LRs (LR>1010). The results suggested that the Precision ID Ancestry Panel provided too little information and that additional markers specifically selected for sub-continental differentiation may be required for accurate population assignment of admixed individuals. Furthermore, a Genogeographer database with additional populations including admixed populations would be advantageous for interpretation of admixed AIM profiles. It would likely increase the number of population assignments and illustrate alternatives to the most likely population, which would be valuable information for the case officer when writing the case report.

Orchid Micropropagation Using Conventional Semi-Solid and Temporary Immersion Systems: A Review.

Orchids, with their astonishingly stunning flowers, dominate the international floricultural market. They are considered prized assets for commercial applications in pharmaceutical and floricultural industries as they possess high therapeutic properties and superior ornamental values. The alarming depletion of orchid resources due to excessive unregulated commercial collection and mass habitat destruction makes orchid conservation measures an extreme priority. Conventional propagation methods cannot produce adequate number of orchids, which would meet the requirement of these ornamental plants for commercial and conservational purposes. In vitro orchid propagation using semi-solid media offers an outstanding prospect of rapidly producing quality plants on a large scale. However, the semi-solid (SS) system has shortcomings with low multiplication rates and high production costs. Orchid micropropagation using a temporary immersion system (TIS) overcomes the limitations of the SS system by reducing production costs and making scaleup and full automation possible for mass plant production. The current review highlights different aspects of in vitro orchid propagation using SS and TIS and their benefits and drawbacks on rapid plant generation.

Longitudinal changes and variation in human DNA methylation analysed with the Illumina MethylationEPIC BeadChip assay and their implications on forensic age prediction.

DNA methylation, a pivotal epigenetic modification, plays a crucial role in regulating gene expression and is known to undergo dynamic changes with age. The present study investigated epigenome-wide methylation profiles in 64 individuals over two time points, 15 years apart, using the Illumina EPIC850k arrays. A mixed-effects model identified 2821 age-associated differentially methylated CpG positions (aDMPs) with a median rate of change of 0.18% per year, consistent with a 10-15% change during a human lifespan. Significant variation in the baseline DNA methylation levels between individuals of similar ages as well as inconsistent direction of change with time across individuals were observed for all the aDMPs. Twenty-three of the 2821 aDMPs were previously incorporated into forensic age prediction models. These markers displayed larger changes in DNA methylation with age compared to all the aDMPs and less variation among individuals. Nevertheless, the forensic aDMPs also showed inter-individual variations in the direction of DNA methylation changes. Only cg16867657 in ELOVL2 exhibited a uniform direction of the age-related change among the investigated individuals, which supports the current knowledge that CpG sites in ELOVL2 are the best markers for age prediction.

Analysis of 12 X-STRs in Greenlanders, Danes and Somalis using Argus X-12.

X-chromosome markers have become a useful set of markers of choice when certain complex kinship cases need to be unravelled. The Argus X-12 kit allows the co-amplification in a single PCR reaction of 12 X-chromosome short tandem repeats located in four linkage groups. A number of 507 unrelated individuals from Greenland, Denmark and Somalia together with two generation families were typed using the Argus X-12 kit. Silent alleles for the DXS10148 and DXS10146 systems were observed in males, mostly from Somalia. High levels of intrapopulation variability and therefore high forensic parameter values were calculated for the three studied populations. The population in Greenland showed a significantly lower intrapopulation variability and a high genetic differentiation compared with 13 other populations. Significant levels of linkage disequilibrium were observed between markers belonging to the same linkage group, mainly in the populations in Greenland and Somalia. Family studies allowed the calculation of mutation and recombination frequencies. A higher male versus female mutation rate was obtained, with an average value of 3.3 × 10(-3). Recombination fraction calculations performed on two generation families showed, as previously described, a not complete independence between X-chromosome linkage groups 3 and 4.

A method for the analysis of 32 X chromosome insertion deletion polymorphisms in a single PCR.

Studies of human genetic variation predominantly use short tandem repeats (STRs) and single nucleotide polymorphisms (SNPs) but Insertion deletion polymorphisms (Indels) are being increasingly explored. They combine desirable characteristics of other genetic markers, especially the possibility of being analysed using short amplicon strategies, which increases the ease of analysis, contributing to justify their interest in population and forensic genetics. After the advent of autosomal and uniparental genomes (mtDNA and Y chromosome), these fields of research are also focusing on the X chromosome, given its special transmission pattern. The X chromosome markers brought new insights into the history of modern human populations and also proved useful in forensic kinship investigations, namely in deficient relationship cases and in cases where autosomes are uninformative. This work describes an X-Indel multiplex system amplifying 32 biallelic markers in one single PCR. The multiplex includes X-Indels shown to be polymorphic in the major human population groups and follows a short amplicon strategy. The set was applied in the genetic characterization of sub-Saharan African, European and East Asian population samples and revealed high forensic efficiency, as measured by the accumulated power of discrimination (0.9999990 was the lowest value in males and 0.999999999998 was the highest in females) and mean exclusion chance varied between 0.998 and 0.9996 in duos and between 0.99997 and 0.999998 in trios. Finally, a segregation analysis was performed using trio constellations of father-mother-daughters in order to address the transmission pattern and assess mutation rates of this type of markers.

Refining the genetic portrait of Portuguese Roma through X-chromosomal markers.

Due to differences in transmission between X-chromosomal and autosomal DNA, the comparison of data derived from both markers allows deeper insight into the forces that shape the patterns of genetic diversity in populations. In this study, we applied this comparative approach to a sample of Portuguese Roma (Gypsies) by analyzing 43 X-chromosomal markers and 53 autosomal markers. Portuguese individuals of non-Gypsy ancestry were also studied. Compared with the host population, reduced levels of diversity on the X chromosome and autosomes were detected in Gypsies; this result was in line with known patterns of genetic diversity typical of Roma groups. As a consequence of the complex demographic past of the Roma, during which admixture and genetic drift played major roles, the amount of linkage disequilibrium (LD) on the X chromosome in Gypsies was considerably higher than that observed in non-Gypsies. When the pattern of differentiation on the X chromosome was compared with that of autosomes, there was evidence for asymmetries in female and male effective population sizes during the admixture between Roma and non-Roma. This result supplements previous data provided by mtDNA and the Y chromosome, underlining the importance of using combined information from the X chromosome and autosomes to dissect patterns of genetic diversity. Following the out-of-India dispersion, the Roma acquired a complex genetic pattern that was influenced by drift and introgression with surrounding populations, with important contributions from both males and females. We provide evidence that a sex-biased admixture with Europeans is probably associated with the founding of the Portuguese Gypsies.

Safety and Quality of Canned Sardines after Opening: A Shelf-Stability Study.

This study aimed to define the shelf life of canned sardines after opening to increase consumer awareness of their quality and safety and reduce food waste. For this purpose, canned sardines (Sardina pilchardus) packed with different sauces were opened and stored at 4 °C for 7 days. Microbiological, sensorial, physical and chemical stability was monitored daily by standard methodologies. Results show that the overall quality and safety are highly dependent on the sauce type. To preserve their full quality, sardines in brine and in vegetable oil should be consumed up to 1 day after opening, while sardines in tomato sauce were stable for up to 3 days, although none were considered nonedible up to the 7th day. Many parameters demonstrated statistical differences and correlations with storage, although they were not as decisive as sensory evaluation. This integrated approach should be adopted by the food industry and regulating authorities to provide information to consumers regarding the quality and safety of handled goods.