Connection of the polymorphic variant T174M angiotensinogen gene with coronary atherosclerosis in the Tomsk population

Allele and genotype frequencies of the T174M polymorphism of the angiotensinogen gene were for the first time estimated in the West Siberian population. The polymorphism was tested for association with coronary atherosclerosis (CAS) and with several quantitative risk factors in patients with angiographically verified CAS, healthy individuals, and in a population sample nondifferentiated with respect to CAS.     

Genotyping and haplotyping of polymorphisms directly from genomic DNA via coupled amplification and sequencing (CAS).

Coupled amplification and sequencing (CAS) allows a segment of DNA to be sequenced directly from genomic DNA. An initial PCR amplification stage selects and amplifies the target. During a subsequent stage both strands of the target segment are sequenced simultaneously and amplified further. We show that CAS can readily identify variant base pairs. Genotyping of a population for known sequence variation can be achieved simply and directly from genomic DNA of each organism by performing CAS only for the variant bases. The procedure supercedes development and optimization of alternative typing assays based on oligonucleotide hybridization or ligation. In addition, we show that competitive oligonucleotide priming with allelic primers can be readily performed in concert with the second stage of CAS. The combination of techniques allows sequencing of a single chromosome from a heterozygous genomic sample and direct haplotyping of the polymorphism at the priming site with any others encompassed within the amplified segment.     

Analysis of gene complexes predisposing to coronary atherosclerosis

The following seven polymorphic marker loci of genes responsible for predisposition to coronary atherosclerosis (CAS) were studied: the ACE locus responsible for angiotensin-converting enzyme insertion/deletion polymorphism for the presence or absence of the Alu insertion in the gene; the F13, PLAT, and APOA1 loci, controlling the clotting factor 13, plasminogen-activating tissue factor, and apolipoprotein A, respectively; the MTHFR and AGT polymorphic loci responsible for point mutations in methylenetetrahydrofolate reductase and those in angiotensinogen, respectively, and the NOS3 locus controlling the number of tandem repeats in the nitric oxide synthase gene. These loci are located on different chromosomes and encode products involved into various metabolic pathways leading to CAS. In the populations studied, significant differences between healthy subjects and patients predisposed to cardiovascular diseases were revealed with regard to the above seven markers. The 174M allele (T174M polymorphism in the ACE gene) was significantly associated with coronary atherosclerosis. It was found that specific gene combinations are involved in the CAS development and determine variation in the pathogenetically important quantitative traits.     

Analysis of Gene Complexes Predisposing to Coronary Atherosclerosis

The following seven polymorphic marker loci of genes responsible for predisposition to coronary atherosclerosis (CAS) were studied: the ACE locus responsible for angiotensin-converting enzyme insertion/deletion polymorphism for the presence or absence of the Alu insertion in the gene; the F13,PLAT, and APOA1 loci, controlling the clotting factor 13, plasminogen-activating tissue factor, and apolipoprotein A, respectively; the MTHFR and AGT polymorphic loci responsible for point mutations in methylenetetrahydrofolate reductase and those in angiotensinogen, respectively, and the NOS3 locus controlling the number of tandem repeats in the nitric oxide synthase gene. These loci are located on different chromosomes and encode products involved into various metabolic pathways leading to CAS. In the populations studied, significant differences between healthy subjects and patients predisposed to cardiovascular diseases were revealed with regard to the above seven markers. The 174M allele (T174M polymorphism in the AGT gene) was significantly associated with coronary atherosclerosis. It was found that specific gene combinations are involved in the CAS development and determine variation in the pathogenetically important quantitative traits.     

Examining Levels of Risk Behaviors among Black Men Who Have Sex with Men (MSM) and the Association with HIV Acquisition

Seroadaptation is defined as the practice of modifying sexual behavior based on one’s own HIV serostatus, the perceived HIV serostatus of sexual partners, and differences in risk of HIV transmission by sexual acts. Because this definition implies intent, we use the term “seroprotection” to describe HIV negative participants reporting condomless anal sex (CAS) either exclusively with seronegative partners, or only as the insertive partner with HIV positive or unknown serostatus partners. Little is known about seroprotection in Black men who have sex with men (MSM). We evaluated the independent association of seroprotection and HIV acquisition among the 1144 HIV-negative Black MSM enrolled in HPTN 061 using Cox models; we stratified by city of enrollment, and controlled for number of partners, age, and drug use. Behaviors reported at 0, 6, and 12 months were assigned to three mutually exclusive categories: (1) No CAS; (2) Seroprotection; and (3) CAS without seroprotection. In 2,861 six-month intervals; 28 HIV seroconversions occurred. No CAS was reported at 33.3% of visits, seroprotection at 46.6% of visits, and CAS without seroprotection at 20.1% of visits. The seroconversion rate per 100 person-years for no CAS was 0.98 (95% CI: 0.27, 2.51), compared with 2.39 (95% CI: 1.03, 4.71) and 13.33 (95% CI: 7.62, 21.66) for seroprotection and CAS without seroprotection, respectively. Compared to CAS without seroprotection, intervals without CAS were associated with an 87% reduction (aHR: 0.13, 95% CI: 0.03–0.46) in HIV acquisition and intervals with seroprotection with a 78% reduction (aHR: 0.22, 95% CI: 0.09–0.57). No CAS is the safest behavior to prevent HIV acquisition. Seroprotective behaviors significantly reduced risk, but HIV incidence was still >2/100 person-years, suggesting that additional strategies, such as pre-exposure prophylaxis, are warranted for this population.     

Risk of coronary artery stenosis in Iranian type 2 diabetics: is there a role for matrix metalloproteinase-3 gene (-1612 5A/6A) polymorphism?

Aim  

To investigate the association of matrix metalloproteinase-3 (MMP-3) polymorphism with susceptibility to coronary artery stenosis (CAS) and the number of diseased vessels in patients with type 2 diabetes mellitus (T2DM).     

Population subdivision and the Hudson-Kreitman-Aguade test: testing for deviations from the neutral model in organelle genomes

The Hudson-Kreitman-Aguade (HKA) test is based on the prediction from the neutral theory that levels of polymorphism within a species and the divergence between two closely related species should be correlated. Population subdivision has been shown to alter both the amounts of polymorphism segregating within species and the rate of divergence between species, meaning that genomic regions with different population structures also differ in their divergence to polymorphism ratios. Population subdivision may hence hamper the utility of the HKA test for detecting deviations from the standard neutral model, especially for organelle genomes that often have different patterns of population structure compared with nuclear genes. In this paper, I show that population subdivision inflates the number of instances where the HKA test detects deviations from the neutral model. Using coalescent simulations I show that this bias is most apparent when population subdivision is strong and differs substantially between the loci included. However, if divergence time is large and population structure substantial even changes in the levels of polymorphism and divergence associated with differences in the effective population size between two loci is enough to substantially alter the number of significant outcomes of the HKA test. A dataset on cytoplasmic diversity in Sileine vulgaris and S. latifolia (Ingvarsson & Taylor, 2002) is also reanalysed. The previous study had shown a marked excess of intraspecific polymorphism in both species. However, when effects of population subdivision were removed, ad hoc, levels of intraspecific polymorphism were no longer significantly different from neutral expectations, suggesting that population subdivision contributed to the observed excess of intraspecific polymorphism seen in both species of Silene.     

Measurement of coronaphobia in older adults: Validation of the Spanish version of the Coronavirus Anxiety Scale

Background and objectiveThe Coronavirus Anxiety Scale (CAS) is an instrument that measures the severity of anxiety due to COVID-19 or coronaphobia. In the context of the COVID-19 pandemic, older adults are the most vulnerable age group; therefore, the aim of the study was to evaluate the psychometric properties of the CAS in this group.Materials and method274 Peruvian older adults participated (M_age = 67.86; SD = 6.34, 64.6% women). In addition to the CAS, the 2-item Patient Health Questionnaire (PHQ-2), and 2-item Generalized Anxiety Disorder Scale (GAD-2) were applied. Confirmatory Factor Analysis (CFA) was used to assess the factor structure of the CAS and Item Response Theory was used to analyze item characteristics. A sequence of hierarchical variance models was used to evaluate the measurement invariance of the CAS according to age. To assess reliability, Cronbach's alpha coefficient (α) and the omega coefficient (ω) were used. The correlations between the CAS score and the scores of the PHQ-2 and GAD-2 scales were calculated with Pearson's correlation coefficient (r).ResultsThe results of the CFA indicated that the unidimensional model of the CAS fitted the data adequately and showed very good reliability (α and ω ≥ .83). Likewise, all items provided high information and adequate discrimination, which allowed for better detection of average and high levels of coronaphobia in the older adult population. However, the CAS did not show evidence of being strictly invariant between older adults aged 60–65 years and 66–86 years. The CAS showed significant correlations with anxiety (r = .72; [95%CI: .66, .87] p < .01) and depression (r = .53; [95%CI: .43, .76] p < .01).ConclusionThe CAS in Spanish shows evidence of validity based on internal structure, convergent and divergent validity, as well as an adequate reliability estimate to assess coronaphobia in older adults. The CAS can be used to detect average and high levels of coronaphobia in the older adult population.     

Genetic loads and coadaptivity of chromosomal inversions I. Inversion polymorphism and genetic load on chromosome O in a Drosophila subobscura population from Petnica

Inversion polymorphism on chromosome O and polymorphism for the viability of determining genes have been studied in a natural population of Drosophila subobscura from Petnica (Serbia). The range of inversion polymorphism and the abundance of particular gene arrangements in the study population agree with a general pattern of inversion polymorphism of D. subobscura in Europe. The data obtained on the amount of genetic loads show that the D. subobscura population from Petnica displays a moderate degree of that polymorphism, compared to the other studied populations of these species. Therefore, the D. subobscura population from Petnica could be tentatively classified as an ecologically central population. Examination association of chromosomal, thus, inversion polymorphism with gene polymorphism, in the form of genetic loads show that differences exist in the mean viability among certain gene arrangements. The distribution of deleterious genes among chromosome O gene arrangements were non-random.     

Examples of the effect of genetic variation on competing species

An ordinary differential equation model for two competing populations with genetic variation in one population is presented. The degree of frequency dependence needed to produce various configurations of stable equilibria is discussed. For example, if the fitnesses are frequency independent then there may exist stable polymorphism although the genetically varying population becomes extinct in each fixation plane. Stable polymorphism where the genetically invariant population becomes extinct in each fixation plane requires frequency dependence in the fitness of the genetically invariant population.     

Neuronal competition determines the spatial pattern of neuropeptide expression by identified neurons of the leech.

Staining adult and embryonic leech ventral nerve cords with antibodies raised against the molluscan neuropeptides small cardioactive peptide B (SCP) and FMRFamide results in segment-specific and bilaterally asymmetric patterns of cell staining. One immunoreactive neuron, the RAS interneuron, is present in only four rostral segmental ganglia, while another, the CAS interneuron, is restricted to the four most caudal abdominal ganglia and tail. In addition to their segment-specific distributions, only one RAS or CAS cell is found in each segmental ganglion, and they alternate sides between adjacent ganglia (either L-R-L-R or R-L-R-L) with a fidelity of about 95%. This paper utilizes cell deletion techniques to investigate the determination of the asymmetric and alternating pattern of RAS and CAS neurons. We show that developmentally equivalent RAS and CAS homologs are present on both sides of the appropriate ganglia, and that within each ganglion one of the initially paired homologs loses the ability to assume the immunoreactive RAS or CAS fate 2-3 days after axonogenesis has begun. These experiments suggest that there is a competitive interaction between bilateral homologs which ensures that only one mature RAS/CAS neuron is formed per ganglion, and that contralateral RAS/CAS neurons are not required in the same or adjacent ganglia for the determination of the RAS or CAS developmental pathways. Nerve cord transections between ganglia in the CAS domain can alter the spatial pattern of CAS neuron determination, confirming that both bilateral homologs retain the ability to express neuropeptide until late embryonic stages, and suggesting that the alternating pattern of RAS/CAS cells requires communication between adjacent ganglia through the longitudinal connectives.     

RAPD-PCR analysis of genetic diversity in the Manchurian pheasant

The genetic diversity of a local population of the Manchurian pheasant Phasianus colchicus pallasi was studied using RAPD-PCR. Based on the DNA patterns obtained in PCR with five arbitrary decanucleotide primers, we assessed genetic polymorphism of this population, estimated genetic distances between individuals, and constructed an NJ phylogenetic tree, and an UPGMA dendrogram of genetic similarity. The population was shown to exhibit high average genetic polymorphism (P = 79.4%) and genetic distances (D = 0.267). Possible reasons for the high genetic diversity of this local population are discussed.     

乳腺浸润性导管癌组织中CAS蛋白表达的临床病理意义

目的研究乳腺浸润性导管癌组织中细胞凋亡易感蛋白（CAS）表达的临床病理意义。方法选取乳腺浸润性导管癌53例、普通导管增生20例、异型导管增生20例、导管原位癌10例、正常乳腺组织14例,应用免疫组化方法观察CAS蛋白的表达,并探讨CAS与乳腺癌临床病理因素的关系,分析CAS和HER2、ER、PR以及ki-67指数的关系。结果 CAS在正常乳腺、普通导管增生、异型导管增生、导管原位癌、浸润性导管癌中的阳性率逐渐升高,分别为14.3%、25.0%、40.0%、60%、75.5%（P=0.000）,CAS、HER2均与乳腺癌组织学分级、核分裂像、淋巴结转移有关;CAS评分与ki-67指数（r=0.439,P=0.003）和HER2评分（r=0.598,P=0.000）正相关。结论 CAS与乳腺癌的发生、发展、增殖、淋巴结转移有关,可能作为反映乳腺癌生物学行为的肿瘤标记物,CAS蛋白的表达和HER2有一定的相关性。     

Autosomal and sex-chromosomal polymorphism in a wild population of the Norway rat,Rattus norvegicus

The karyotypes of 33 specimens of Rattus norvegicus captured in a wild population, were studied by means of conventional Giemsa staining and G- and C-banding methods. A chromosomal polymorphism for the presence or absence of extra segments in autosomes 3 and 12 and the X chromosome was found, beside a polymorphism for centromeric C-bands in pair no. 6.The frequency of different chromosome types found in this population was compared with that found in a wild population in Japan as well as with that found in some inbred strains.     

The tyrosine kinase substrate p120cas binds directly to E-cadherin but not to the adenomatous polyposis coli protein or alpha-catenin.

The tyrosine kinase substrate p120cas (CAS), which is structurally similar to the cell adhesion proteins beta-catenin and plakoglobin, was recently shown to associate with the E-cadherin-catenin cell adhesion complex. beta-catenin, plakoglobin, and CAS all have an Arm domain that consists of 10 to 13 repeats of a 42-amino-acid motif originally described in the Drosophila Armadillo protein. To determine if the association of CAS with the cadherin cell adhesion machinery is similar to that of beta-catenin and plakoglobin, we examined the CAS-cadherin-catenin interactions in a number of cell lines and in the yeast two-hybrid system. In the prostate carcinoma cell line PC3, CAS associated normally with cadherin complexes despite the specific absence of alpha-catenin in these cells. However, in the colon carcinoma cell line SW480, which has negligible E-cadherin expression, CAS did not associate with beta-catenin, plakoglobin, or alpha-catenin, suggesting that E-cadherin is the protein which bridges CAS to the rest of the complex. In addition, CAS did not associate with the adenomatous polyposis coli (APC) tumor suppressor protein in any of the cell lines analyzed. Interestingly, expression of the various CAS isoforms was quite heterogeneous in these tumor cell lines, and in the colon carcinoma cell line HCT116, which expresses normal levels of E-cadherin and the catenins, the CAS1 isoforms were completely absent. By using the yeast two-hybrid system, we confirmed the direct interaction between CAS and E-cadherin and determined that CAS Arm repeats 1 to 10 are necessary and sufficient for this interaction. Hence, like beta-catenin and plakoglobin, CAS interacts directly with E-cadherin in vivo; however, unlike beta-catenin and plakoglobin, CAS does not interact with APC or alpha-catenin.     

Frequency-dependent predation and maintenance of prey polymorphism

In positive frequency-dependent predation, predation risk of an individual prey correlates positively with the frequency of that prey type. In a number of small-scale experiments individual predators have shown frequency-dependent behaviour, often leading to the conclusion that a population of such predators could maintain prey polymorphism. Using simulations, I studied the dynamics of frequency-dependent predation and prey polymorphism. The model suggests that persistence of prey polymorphism decreases with increasing number of predators that show frequency-dependent behaviour, questioning conclusions about polymorphism based on experiments with few predators. In addition, prey population size, prey crypsis, difference in crypsis between prey morphs and the way the behaviour was adjusted affected the persistence of polymorphism. Under some circumstances prey population remained polymorphic for a shorter time under frequency-dependent than under frequency-independent predation. This suggests that although positive frequency-dependent predator behaviour may maintain prey polymorphism, it is not a sufficient condition for persistent prey polymorphism.     

Comparison of genetic models for analysing the effects of a PvuII polymorphism in the oestrogen receptor 1 (ESR1) gene on prolificacy in an Iberian x Meishan pig population

The effect of a previously reported PvuII polymorphism in oestrogen receptor 1 (ESR1) was analysed in an F(2) population of Iberian x Meishan pigs. We tested three hypotheses: (1) that a causal mutation was fixed in the parental populations, (2) that a causal mutation existed that was in complete linkage disequilibrium with the alleles of the PvuII polymorphism and (3) that a causal mutation existed in linkage disequilibrium within each parental population. The third model was the most plausible based on the available data. ESR1 alleles displayed different patterns of linkage disequilibrium with the causal mutation in each of the parental populations and the PvuII polymorphism was clearly not the causal mutation. As a consequence, the use of the ESR1 mutation for selection must be evaluated for a particular pig population before it is applied.     

Evaluation of a peripherally selective antiandrogen (Casodex) as a tool for studying the relationship between testosterone and spermatogenesis in the rat.

The endocrine profile and the effects on spermatogenesis of the new antiandrogen, Casodex [2RS)-4-cyano-3-(4-fluorophenylsulphonyl)-2-anilide, CAS) were evaluated in the adult rat. In the first experiment rats were administered CAS at daily doses of 10, 20 and 40 mg/kg for 14 days. For comparison groups receiving flutamide (FL, 10 mg/kg) and ethane dimethane sulphonate (EDS) were included. Unlike FL, administration of CAS (10 and 20 mg/kg) did not significantly raise serum concentrations of gonadotropic hormones and testosterone. With 40 mg/kg CAS gonadotropin secretion, but not testosterone levels, were elevated on day 15. Administration of CAS lowered the weight of the seminal vesicles and coagulating glands comparable to the administration of the Leydig cell toxin EDS. In contrast to FL a significant loss of germ cells in stage VII of spermatogenesis was observed with CAS. In a second experiment the ability of FL and CAS to block testicular androgen action was compared in rats with reduced testicular androgen production induced by a gonadotropin-releasing hormone antagonist. Both antiandrogens markedly enhanced spermatogenic involution as revealed by quantitative flow cytometric analysis of germ cell numbers. The study demonstrates that (a) CAS is a peripherally selective antiandrogen and (b) CAS might provide a feasible approach to study androgen dependence of spermatogenesis in the presence of normal FSH levels.     

Subsets of the major tyrosine phosphorylation sites in Crk-associated substrate (CAS) are sufficient to promote cell migration

Crk-associated substrate (p130(CAS) or CAS) is a major integrin-associated Src substrate that undergoes tyrosine phosphorylation at multiple YXXP motifs in its substrate domain (SD) to create docking sites for SH2-containing signaling effectors. Notably, recruitment of Crk adaptor proteins to the CAS SD sites is implicated in promoting cell migration. However, it is unclear which or how many of the 15 CAS SD YXXP tyrosines are critically involved. To gain a better understanding of CAS SD function, we assessed the signaling capacity of individual YXXP motifs. Using site-directed mutagenesis combined with tryptic phosphopeptide mapping, we determined that the ten tyrosines in YXXP motifs 6-15 are the major sites of CAS SD phosphorylation by Src. Phosphopeptide binding assays showed that all of these sites are capable of binding the Crk SH2 domain. To evaluate the requirement for CAS YXXP sites in stimulating cell migration, a series of phenylalanine substitution variants were expressed in CAS -/- mouse embryo fibroblasts. CAS expression enhanced the rate of cell migration into a monolayer wound in a manner dependent on the major sites of Src phosphorylation. Effective wound healing was achieved by CAS variants containing as few as four of the major sites, indicating sufficiency of partial SD signaling function in this cell migration response.     

Constraints on the origin and maintenance of genetic kin recognition

Kin-recognition mechanisms allow helping behaviors to be directed preferentially toward related individuals, and could be expected to evolve in many cases. However, genetic kin recognition requires a genetic polymorphism on which recognition is based, and kin discriminating behaviors will affect the evolution of such polymorphism. It is unclear whether genetic polymorphisms used in kin recognition should be maintained by extrinsic selection pressures or not, as opposite conclusions have been reached by analytical one-locus models and simulations exploring different population structures. We analyze a two-locus model in a spatially subdivided population following the island model of dispersal between demes of finite size. We find that in the absence of mutation, selection eliminates polymorphism in most cases, except with extreme spatial structure and low recombination. With mutation, the population may reach a stable limit cycle over which both loci are polymorphic; however, the average frequency of conditional helping can be high only under strong structure and low recombination. Finally, we review evidence for extrinsic selection maintaining polymorphism on which kin recognition is based.