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The Y-STR DYS19 is firmly established in the repertoire of Y-chromosomal markers used in forensic analysis yet is poorly understood at the molecular level, lying in a complex genomic environment and exhibiting null alleles, as well as duplications and occasional triplications in population samples. Here, we analyse three null alleles and 51 duplications and show that DYS19 can also be involved in inversion events, so that even its location within the short arm of the Y chromosome is uncertain. Deletion mapping in the three chromosomes carrying null alleles shows that their deletions are less than approximately 300 kb in size. Haplotypic analysis with binary markers shows that they belong to three different haplogroups and so represent independent events. In contrast, a collection of 51 DYS19 duplication chromosomes belong to only four haplogroups: two are singletons and may represent somatic mutation in lymphoblastoid cell lines, but two, in haplogroups G and C3c, represent founder lineages that have spread widely in Central Europe/West Asia and East Asia, respectively. Consideration of candidate mechanisms underlying both deletions and duplications provides no evidence for the involvement of non-allelic homologous recombination, and they are likely to represent sporadic events with low mutation rates. Understanding the basis and population distribution of these DYS19 alleles will aid in the utilisation and interpretation of profiles that contain them.

We have previously shown that the Y chromosomes of 'white' Brazilians have their immediate geographical origin in Europe, with low frequency of sub-Saharan African chromosomes and virtual absence of Amerindian contribution. The typing of slow evolving polymorphisms on the Y chromosome also revealed no differences between Brazilians and Portuguese, the bulk of European immigrants to Brazil, and even among Brazilians from distinct regions of Brazil, the latter being in sharp contrast with mtDNA data. In order to test if the lack of differentiation is a sex-biased and not a marker-biased phenomenon, we decided to study faster evolving Y chromosome markers in samples from Brazil and Portugal previously studied. The population structure revealed by this work confirmed that there were indeed no significant differences between Brazil and Portugal and no population differentiation within the four geographical regions of Brazil, suggesting that this phenomenon is unrelated to the nature of the markers typed. Nevertheless the fast evolving markers did uncover a higher within population diversity in Brazil than Portugal, which could be explained by the input of diverse European Y chromosomes carried by several migration waves to Brazil. Our present data highlight the significance of typing and combining Y markers that evolve according to distinct mutational paces to usefully assess the levels of diversity in a given population, and can be applied in the study of populations derived from distinct geographical origins such as the Brazilians.

In eutherians, the sex-reversing ATRX gene on the X has no homologue on the Y chromosome. However, testis-specific and ubiquitously expressed X-borne genes have been identified in Australian marsupials. We studied nucleotide sequence and chromosomal location of ATRX homologues in two American marsupials, the opossums Didelphis virginiana and Monodelphis domestica. A PCR fragment of M. domestica ATRX was used to probe Southern blots and to screen male genomic libraries. Southern analysis demonstrated ATRX homologues on both X and Y in D. virginiana, and two clones were isolated which hybridized to a single position on the Y chromosome in male-derived cells but to multiple sites of the X in female cells. In M. domestica, there was a single clone that mapped to the X but not to the Y, suggesting that it represents the M. domestica ATRX. However a male-specific band was detected in Southern blots probed with the D. virginiana ATRY and with a mouse ATRX clone, which implies that the Y copy in M. domestica has diverged further from other ATRX homologues. Thus there appears to be a Y-borne copy of ATRY in American, as well as Australian marsupials, although it has diverged in sequence, as have other Y genes that are testis-specific in both eutherian and marsupial lineages.

In this work, we analyze several characteristics influencing the low variability of the microsatellite DYS19 in the major founder Amerindian Y chromosome lineage containing the point mutation DYS199-T. Variation of DYS19 was compared with that of five other Y-linked tetranucleotide repeat loci (DYS389A, DYS389B, DYS390, DYS391, and DYS393) in the DYS199-T lineage. All the other microsatellites showed significantly higher levels of variability than DYS19 as measured by gene diversity and repeat number variance. Moreover, we had previously shown that DYS19 had high diversity in Brazilians and in several other populations worldwide. Thus, the slow DYS19 evolution in the DYS199-T lineage seems to be both locus and allele specific. To understand the slow DYS19 evolutionary rate, the microsatellite loci were compared according to their mapping on the Y chromosome and also on the basis of structural aspects such as the base composition of the repeat motif and flanking regions and the degree of perfection and size (repeat number) of the variable blocks. The only observed difference that might be related to the low DYS19 variability is its small average number of repeats, a value expected to be closer to the founder DYS19 allele in the DYS199-T lineage. These data were also compared to other derived Y lineages. The Tat-C lineage displayed a lower DYS19 variability correlated to a small average repeat number, while in the DYS234-G lineage, a high DYS19 variability was found associated to a larger average repeat number. This approach reveals that evolution of Y microsatellites in lineages defined by slowly evolving markers, such as point mutations, can be greatly influenced by the size (number of repeats of the variable block) of the founder allele in each microsatellite locus. Thus lineage-dating methods using microsatellite variation should be practiced with great care.

Background The domestic pig is known as an excellent model for human immunology and the two species share many pathogens. Susceptibility to infectious disease is one of the major constraints on swine performance, yet the structure and function of genes comprising the pig immunome are not well-characterized. The completion of the pig genome provides the opportunity to annotate the pig immunome, and compare and contrast pig and human immune systems. Results The Immune Response Annotation Group (IRAG) used computational curation and manual annotation of the swine genome assembly 10.2 (Sscrofa10.2) to refine the currently available automated annotation of 1,369 immunity-related genes through sequence-based comparison to genes in other species. Within these genes, we annotated 3,472 transcripts. Annotation provided evidence for gene expansions in several immune response families, and identified artiodactyl-specific expansions in the cathelicidin and type 1 Interferon families. We found gene duplications for 18 genes, including 13 immune response genes and five non-immune response genes discovered in the annotation process. Manual annotation provided evidence for many new alternative splice variants and 8 gene duplications. Over 1,100 transcripts without porcine sequence evidence were detected using cross-species annotation. We used a functional approach to discover and accurately annotate porcine immune response genes. A co-expression clustering analysis of transcriptomic data from selected experimental infections or immune stimulations of blood, macrophages or lymph nodes identified a large cluster of genes that exhibited a correlated positive response upon infection across multiple pathogens or immune stimuli. Interestingly, this gene cluster (cluster 4) is enriched for known general human immune response genes, yet contains many un-annotated porcine genes. A phylogenetic analysis of the encoded proteins of cluster 4 genes showed that 15% exhibited an accelerated evolution as compared to 4.1% across the entire genome. Conclusions This extensive annotation dramatically extends the genome-based knowledge of the molecular genetics and structure of a major portion of the porcine immunome. Our complementary functional approach using co-expression during immune response has provided new putative immune response annotation for over 500 porcine genes. Our phylogenetic analysis of this core immunome cluster confirms rapid evolutionary change in this set of genes, and that, as in other species, such genes are important components of the pig’s adaptation to pathogen challenge over evolutionary time. These comprehensive and integrated analyses increase the value of the porcine genome sequence and provide important tools for global analyses and data-mining of the porcine immune response.

The Human and Vertebrate Analysis and Annotation (HAVANA) group at the Wellcome Trust Sanger Institute produced the manually annotated geneset for the Encyclopedia of DNA Elements (ENCODE) pilot project and, as part of the Gencode subgroup, are reprising this role in the scale up to cover the whole human genome. Our manual annotation is checked computationally and validated experimentally. Loci and transcripts predicted to be absent from the initial annotation are identified by comparison with a number of state-of-the-art algorithms for identifying exons, splice sites, transcripts and pseudogenes. Where novel features are confirmed the annotation is updated. Annotated coding transcripts are analysed to assess their coding potential by investigating patterns of conservation within the coding sequence (CDS) and comparing predicted secondary structures of annotated CDSs to similar proteins with solved structures. Annotated coding transcripts are also checked against the current set of human Consensus CDSs (CCDS) to check agreement with other participating centres (EBI, NCBI, & UCSC).An initial round of annotation and analysis of chromosomes 21 and 22 has shown that while HAVANA annotation is both comprehensive and robust, it has benefitted from computational review. 13 novel non-coding loci, 27 novel splice variants and 6 extensions to existing variants were identified, many of which were found using supporting EST/mRNA sequences that were not present at the time of initial annotation. Fewer than 10 annotated CDSs required reclassification, no CCDS sequences required updating and 26 novel pseudogene were added. The annotation of human chromosome 2 is complete and we are currently annotating chromosomes 3 and 7. Data from all members of Gencode is distributed via DAS and is now visible in our Zmap annotation interface, allowing assessment of computational predictions contemporaneous with first-pass gene annotation.

Manual annotation‭ (‬the‭ "‬museum‭" ‬model of annotation‭) ‬relies on a small group of specialized curators to catalogue and classify genes according to their functional roles.‭ This‬ is both costly and time consuming and therefore is used only for model organisms with sufficient funding.‭ ‬Smaller research communities often have to rely on other models of annotation,‭ ‬mainly automated annotation‭ (‬the‭ "‬factory‭" ‬model,‭ ‬e.g.‭ ‬Ensembl‭)‬,‭ ‬and the‭ "‬jamboree‭" ‬model‭ (‬in which a group of leading biologists from the community and bioinformaticians come together for a short intensive annotation workshop‭)‬.‭ ‬At the Wellcome Trust Sanger Institute‭ (‬WTSI‭)‬,‭ ‬the Havana team provides high quality manual annotation of finished vertebrate genome sequences,‭ ‬namely human,‭ ‬mouse and zebrafish.‭ ‬We also perform the curation of specific finished regions such as the MHC in dog,‭ ‬cow and pig,‭ ‬whose whole genomes have been‭ ‬assembled from unfinished BACs or from whole genome shotgun sequences.‭ ‬In addition,‭ ‬we at Havana have also hosted annotation jamborees for the cow‭ (‬Bos taurus‭) ‬and pig‭ (‬Sus scrofa‭) ‬genomes.‭ ‬During those sessions,‭ ‬the research community had the opportunity to annotate their genes of interest under expert guidance using the custom written publicly available Otterlace annotation system,‭ ‬and the unified manual annotation guidelines.‭ ‬By making use of the tools and skills acquired during the cow and pig jamborees,‭ ‬the delegates can continue annotating their genomes remotely.‭ ‬For the pig genome,‭ ‬a highly contiguous physical map has been generated by an international effort of four laboratories (available in Pre!Ensembl) and‭ ‬is being used as a substrate for the swine genome sequencing project.‭ ‬Upcoming vertebrate genomes will be sequenced to a high depth coverage with the next generation sequencing technologies‭ (‬e.g.‭ ‬Illumina,‭ ‬454,‭ ‬SOLiD‭) ‬but will have the drawback of not being manually finished.‭ ‬Manual annotation will be more accurate than the automated predictions at coping with any assembly problems derived from these high coverage but unfinished‭ (‬or automatic pre-finished‭) ‬genomes.‭ ‬Once these inherent assembly errors are corrected and the gene structures are accurately identified with manual annotation,‭ ‬the curated genes will be incorporated and merged with the predicted gene models in Ensembl to provide a unified view of the landscape of vertebrate genomes.‭ ‬I will present an introduction to our manual annotation system and our experience using it for annotation jamborees at the WTSI.

This article is part of the supplement: Beyond the Genome: The true gene count, human evolution and disease genomics, Boston, MA, USA. 11-13 October 2010., The GENCODE consortium is a sub group of the ENCODE consortium. Its aim is to provide complete annotation of genes in the human genome including protein-coding loci, non-coding loci and pseudogenes, based on experimental evidence. The final aim is for the HAVANA team to manually annotate the complete genome. This is a time-consuming process which will be completed over the course of the ENCODE project. Currently, to provide a set of annotation covering the complete genome, rather than just the regions that have been manually annotated, a merge of manual annotation from HAVANA with automatic annotation from the Ensembl automatically annotated gene set is created. This process also adds unique full-length CDS predictions from the Ensembl protein coding set into manually annotated genes, to provide the most complete up to date annotation of the genome possible. Also included in the set are short and long ncRNA genes predicted by the Ensembl prediction pipelines and a consensus set of pseudogene predictions agreed between Havana, Yale and UCSC. The CCDS set is also fully represented within the GENCODE set. The GENCODE set is the default annotation available in Ensembl and is also available in the UCSC genome browser. All the annotation is tagged as to whether it is produced by manual annotation alone, automatic annotation alone, or by both approaches. We are currently working to provide confidence levels for annotation, based on depth and type of evidence supporting it.