The spontaneously hypertensive rat and the stroke-prone spontaneously hypertensive rat are useful models for human hypertension. In these strains hypertension is a polygenic trait, in which both autosomal and sex-linked genes can influence blood pressure. Linkage studies in crosses between the stroke-prone spontaneously hypertensive rat and the normotensive control strain Wistar-Kyoto have led to the localization of two genes, BP/SP-1 and BP/SP-2, that contribute significantly to blood pressure variation in the F2 population. BP/SP-1 and BP/SP-2 were assigned to rat chromosomes 10 and X, respectively. Comparison of the human and rat genetic maps indicates that BP/SP-1 could reside on human chromosome 17q in a region that also contains the angiotensin I-converting enzyme gene (ACE). This encodes a key enzyme of the renin-angiotensin system, and is therefore a candidate gene in primary hypertension. A rat microsatellite marker of ACE was mapped to rat chromosome 10 within the region containing BP/SP-1.

A sustained increase in pulsatile release of gonadotrophin releasing hormone (GnRH) from the hypothalamus is an essential, final event that defines the initiation of mammalian puberty. This increase depends on coordinated changes in transsynaptic and glial-neuronal communication, consisting of activating neuronal and glial excitatory inputs to the GnRH neuronal network and the loss of transsynaptic inhibitory tone. It is now clear that the prevalent excitatory systems stimulating GnRH secretion involve a neuronal component consisting of excitatory amino acids (glutamate) and at least one peptide (kisspeptin), and a glial component that uses growth factors and small molecules for cell-cell signaling. GABAergic and opiatergic neurons provide transsynaptic inhibitory control to the system, but GABA neurons also exert direct excitatory effects on GnRH neurons. The molecular mechanisms that provide encompassing coordination to this cellular network are not known, but they appear to involve a host of functionally related genes hierarchically arranged. We envision that, as observed in other gene networks, the highest level of control in this network is provided by transcriptional regulators that, by directing expression of key subordinate genes, impose an integrative level of coordination to the neuronal and glial subsets involved in initiating of the pubertal process. The use of high-throughput and gene manipulation approaches coupled to systems biology strategies should provide not only the experimental bases supporting this concept, but also unveil the existence of crucial components of network control not yet identified.

We dissected the complete genome sequence of the O1 serotype strain Vibrio anguillarum 775(pJM1) and determined the draft genomic sequences of plasmidless strains of serotype O1 (strain 96F) and O2␤ (strain RV22) and V. ordalii. All strains harbor two chromosomes, but 775 also harbors the virulence plasmid pJM1, which carries the anguibactin-producing and cognate transport genes, one of the main virulence factors of V. anguillarum. Genomic analysis identified eight genomic islands in chromosome 1 of V. anguillarum 775(pJM1) and two in chromosome 2. Some of them carried potential virulence genes for the biosynthesis of O antigens, hemolysins, and exonucleases as well as others for sugar transport and metabolism. The majority of genes for essential cell functions and pathogenicity are located on chromosome 1. In contrast, chromosome 2 contains a larger fraction (59%) of hypothetical genes than does chromosome 1 (42%). Chromosome 2 also harbors a superintegron, as well as host "addiction" genes that are typically found on plasmids. Unique distinctive properties include homologues of type III secretion system genes in 96F, homologues of V. cholerae zot and ace toxin genes in RV22, and the biofilm formation syp genes in V. ordalii. Mobile genetic elements, some of them possibly originated in the pJM1 plasmid, were very abundant in 775, resulting in the silencing of specific genes, with only few insertions in the 96F and RV22 chromosomes.Vibrio anguillarum is a marine pathogen that causes vibriosis in close to 50 species of fish, including cultured and wild fish, mollusks, and crustaceans, in marine, brackish, and fresh water (1). Vibriosis is a hemorrhagic septicemia with dire consequences for fish rearing, especially in countries that depend heavily on fish for their food consumption. Despite the fact that V. anguillarum is a dramatic cause of vibriosis in fish, little is known about the genomic composition of this important pathogen. Although 23 serotypes have been reported in V. anguillarum, the O1 and O2 serotypes are the major causative agent of fish vibriosis (32,66,75). Many O1 serotype strains harbor 65-kb pJM1-type plasmids, which carry the siderophore anguibactin biosynthesis and transport genes, a main virulence factor of V. anguillarum, while one of the O1 serotype strains and other serotypes, such as all of the O2 strains, are plasmidless (1, 13, 33, 76). Many virulence factors have been characterized, but we are still far from getting the whole picture of the virulence mechanisms of this pathogen (1, 50). The fact that the pJM1 plasmid is an important component of virulence for the 775 strain but that the other three strains examined do not harbor this plasmid and are still virulent indicates that they must have different mechanisms to cause disease. Moreover, O1 serotype strains cause disease in salmonid fish, whereas O2␤ strains are usually isolated from cod and other nonsalmonids (1, 32, 43). We have previously performed random genome sequencing of V. anguillarum 775 genomic DNA and identified potent...

We present a high resolution radiation hybrid map of human chromosome 11 using 506 sequence tagged sites (STSs) scored on a panel of 86 radiation hybrids. The 506 STSs fall into 299 unique positions (average resolution of about 480 kilobases (kb)) that span the whole chromosome. A subset of 260 STSs (143 positions) form a framework map that has a resolution of approximately 1 megabase between adjacent positions and is ordered with odds of at least 1,000:1. The centromere was clearly defined with pericentric markers unambiguously assigned to the short or long arm. The map contains most genes (125) and expressed sequence tags (26) currently assigned to chromosome 11 and more than half of the STSs are polymorphic microsatellite loci. These markers and the map can be used for high resolution physical and genetic mapping.

Multilocus linkage analysis of 62 family pedigrees with X chromosome-linked retinitis pigmentosa (XLRP) was undertaken to determine the presence of possible multiple disease loci and to reliably estimate their map location. Multilocus homogeneity tests furnished convincing evidence for the presence of two XLRP loci, the likelihood ratio being 6.4 x 109:1 in favor of two versus a single XLRP locus and gave accurate estimates for their map location. In 60-75% of the families, location of an XLRP gene was estimated at 1 centimorgan distal to OTC, and in 25-40% ofthe families, an XLRP locus was located halfway between DXS14 (p58-1) and DXZJ (Xcen), with an estimated recombination fraction of 25% between the two XLRP loci. There is also good evidence for a third XLRP locus, midway between DXS28 (C7) and DXS164 (pERT87), supported by a likelihood ratio of 293:1 for three versus two XLRP loci.Retinitis pigmentosa (RP) is a group of hereditary progressive disorders of the retina characterized initially by night blindness, often within the first two decades of life, reduction of peripheral or side vision, eventual decrease in central vision to variable degrees, in many cases leading to total blindness due to degeneration of the retina (1). There are several subtypes of RP, including autosomal recessive, autosomal dominant, and X chromosome-linked forms (XLRP).Linkage analyses in families with XLRP have shown conflicting results regarding the location of the disease locus. Consequently, the presence of two XLRP loci was hypothesized (2-5). One subtype of XLRP, referred to as RP2, was linked to locus DXS7 (L1.28) (6, 7); another subtype, RP3, was linked to locus OTC (ornithine carbamoyltransferase) (8-10). Further evidence for location of an XLRP locus distal to OTC came from a patient with a deletion starting between OTC and DXS84 (754) and extending toward the telomere, in whom several X-chromosome linked diseases occurred including RP (11). Friedrich et al. (12) found another locus responsible for XLRP to be closely linked to DXS7, between Xcen and DXS7 (L1.28).The current study was initiated as a collaborative effort (i) to obtain evidence for XLRP heterogeneity if at all present, and, if so, (ii) to localize the disease loci in a comprehensive linkage and heterogeneity analysis.Family Data. A total of 62 families were available for this analysis, most but not all of which have been published previously. For calculation efficiency, some pedigrees had earlier been broken down into smaller families and analyzed separately; here, they were analyzed undivided. Disease status for both affected males and carrier females was determined by the investigators and was incorporated unaltered in this analysis.In many cases, heterozygous women also have symptoms that are, however, generally much milder than in men. Where detectable, such symptoms have been used for carrier status determination.Linkage Analysis. The linkage analysis was carried out with the LINKAGE programs version 4.7 (13). Map distances between markers whos...

Pancreatic ductal adenocarcinoma (PDAC) has traditionally been thought of as an immunologically quiescent tumor type presumably because of a relatively low tumor mutational burden (TMB) and poor responses to checkpoint blockade therapy. However, many PDAC tumors exhibit T cell inflamed phenotypes. The presence of tertiary lymphoid structures (TLS) has recently been shown to be predictive of checkpoint blockade response in melanomas and sarcomas, and are prognostic for survival in PDAC. In order to more comprehensively understand tumor immunity in PDAC patients with TLS, we performed RNA-seq, single and multiplex IHC, flow cytometry and predictive genomic analysis on treatment naïve, PDAC surgical specimens. Forty-six percent of tumors contained distinct T and B cell aggregates reflective of “early-stage TLS” (ES-TLS), which correlated with longer overall and progression-free survival. These tumors had greater CD8 + T cell infiltration but were not defined by previously published TLS gene-expression signatures. ES-TLS + tumors were enriched for IgG1 class-switched memory B cells and memory CD4 + T cells, suggesting durable immunological memory persisted in these patients. We also observed the presence of active germinal centers (mature-TLS) in 31% of tumors with lymphocyte clusters, whose patients had long-term survival (median 56 months). M-TLS-positive tumors had equivalent overall T cell infiltration to ES-TLS, but were enriched for activated CD4 + memory cells, naive B cells and NK cells. Finally, using a TCGA-PDAC dataset, ES-TLS + tumors harbored a decreased TMB, but M-TLS with germinal centers expressed significantly more MHCI-restricted neoantigens as determined by an in silico neoantigen prediction method. Interestingly, M-TLS + tumors also had evidence of increased rates of B cell somatic hypermutation, suggesting that germinal centers form in the presence of high-quality tumor neoantigens leading to increased humoral immunity that confers improved survival for PDAC patients. Abbreviations TLS: tertiary lymphoid structures; GC: germinal center(s); PDAC: pancreatic ductal adenocarcinoma; RNA-seq: RNA sequencing; BCRseq: B cell receptor sequencing; HEV: high endothelial venule; PNAd: peripheral node addressin; TMB: tumor mutational burden; TCGA: the cancer genome atlas; PAAD: pancreatic adenocarcinoma; FFPE: formalin fixed paraffin embedded; TIME: tumor immune microenvironment.

Much has been learned in recent years about the central mechanisms controlling the initiation of mammalian puberty. It is now clear that this process requires the interactive participation of several genes. Using a combination of high throughput, molecular, and bioinformatics strategies, in combination with a system biology approach, we singled out from the hypothalamus of nonhuman primates and rats a group of related genes whose expression increases at the time of female puberty. Although these genes [henceforth termed tumorrelated genes ( D URING THE LAST few years, significant progress has been made toward elucidating the basic cellular and molecular mechanisms underlying the neuroendocrine control of mammalian puberty. Specific transsynaptic and gliato-neuron communication pathways affecting the GnRH neuronal network have been identified, and the relative importance of each of these pathways in controlling the pubertal process has been demonstrated, along with some of their structural and functional interactions. The neuronal networks most critically involved in controlling GnRH release during sexual development have been shown to be those that use excitatory/inhibitory amino acids (reviewed in Ref. 1), and the recently identified neuropeptide metastin/ kisspeptin (2, 3), for neurotransmission. Cell-cell signaling molecules that, produced in astroglial cells, facilitate GnRH secretion have been identified, and genetic approaches have been used to define the physiological contribution of these molecules to the pubertal process (reviewed in Ref. 4).These efforts have also made clear that no isolated pathway or cellular subset is responsible for the neuroendocrine control of puberty. Instead, this control is likely exerted by complex regulatory gene networks composed of functional modules. A global approach for the system-level identification of such networks has never been attempted, essentially due to the lack of appropriate technology and the relative paucity of genetic and biochemical details that can be assimilated into a testable biological model. The emergence of high-throughput approaches and computational methods to organize, display, and analyze the plethora of results derived from such approaches is rapidly changing this landscape and giving us for the first time the opportunity of identifying functional genetic modules involved in the hierarchical control of puberty.Although mathematical models for common mechanisms of gene regulation are available (see, for instance, Ref. 5), most current models of genetic network architecture derive from nonmammalian species in which single metabolic or developmental pathways have been analyzed (e.g. Refs. 6 -8). The development of similar models to explain integrated functions of much more complex tissues, such as the hypothalamus, has been (and continues to be) exceedingly difficult because of the cellular heterogeneity of the nervous tissue, the lack of adequate sets of biochemical and genetic markers that can be used to build the network, the complexity of the...

The role of the kidney in initiating hypertension has been much debated. Here we demonstrate that a recently identified gene of yet unknown function, termed SA, which is differentially expressed in the kidney of the spontaneously hypertensive rat, cosegregates with an increase in blood pressure in F2 rats derived from a cross of the spontaneously hypertensive rat with normotensive Wistar-Kyoto rats, accounting for 28 and 21% of the genetic variability in systolic and diastolic blood pressures, respectively. Further, the genotype at this locus appears to determine the level of expression of the gene in the kidney. The findings provide strong evidence for a primary genetic involvement of the kidney in hypertension. (J. Clin. Invest. 1993.