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A renewed and new population study of fourteen short tandem repeat loci (TH01, TPOX, CSF1P0, vWA, FES/FPS, F13A01, D13S317, D7S820, D16S539, LPL, F13B, CD4, D5S818 and D8S1179) were performed in a sample of 296-531 unrelated individuals from Serbia and Montenegro. Population data were compared to previously published data from Vojvodina province and neighboring Croatia.
Allele frequencies for the 15 autosomal STR loci included in the AmpFlSTR((R)) IdentifilerTM PCR Amplification Kit panel from Applied Biosystems (D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, TH01, TPOX, CSF1PO, D19S433, D2S1338, D16S539) and several statistical parameters were estimated from a sample of 103 unrelated individuals, mostly Shia and Sunni Arabs, living in most of central and southern Iraq provinces. We compared the allele frequency spectrum detected in the Iraqi population to allele frequencies from 11 other data sets from published studies of individuals from Turkey, Iraqi-Kurdistan, Saudi Arabia, Arab Emarates, Oman, Iran, Syria, and Jordan. Significant global differences in allele frequencies were detected in 9 of the 11 comparisons following sequential Bonferroni corrections. Comparisons with the two independent panels from Saudi Arabia were not significant after applying Bonferroni corrections, however, low P-values (P<0.05) associated with these two contrasts nonetheless suggested that at least slight genetic differences between populations may exist.
Allele frequencies of the 15 STR loci were determined in 208 unrelated individuals from Han population living in Henan, China (central China). All loci except D5S818 were found no deviation from Hardy-Weinberg equilibrium. The combined power of discrimination (PD) and the combined chance of exclusion (CE) for the 15 studied loci were >0.9999999 and 0.999996119, respectively. Our data were statistically compared with the previously reported data from other Chinese population groups, and significant difference was found between central Han Chinese (n=208) and eastern Chinese (n=100) at vWA, or between central Han Chinese (n=208) and southeast Chinese (n=122) at D13S317.
Critical tests (91) were done between 1977 and 1992 in Shetland ponies to evaluate drug susceptibility and population dynamics (present paper) of endoparasites. The test ponies, most less than 1 year old, were from a herd where older animals were treated every 8 weeks initially with cambendazole (CBZ) (1974-1978) and then with oxibendazole (OBZ) (1978-1992). Previous field test data (1974-1992) on older ponies in the breeding herd indicated the presence of benzimidazole (BZ) resistant small strongyles. Data on population dynamics from the present critical tests indicated that 28 species of small strongyles persisted over the study period in spite of initial susceptibility and later refractiveness of six species to both CBZ and OBZ. Changes in intensities and other aspects were observed for the six BZ-resistant species (Cyathostomum catinatium, Cyathostomum coronatum, Cylicocyclus nassatus, Cylicostephanus calicatus, Cylicostephanus goldi, and Cylicostephanus longibursatus). Variabilities, some striking, were found in prevalence and intensity in bots, stomach worms, ascarids, eyeworms, large strongyles, pinworms and tapeworms.
OBJECTIVES: The aim of this study was to assess the prevalence and risk factors for coronary artery disease (CAD) in a native urban South Indian population. BACKGROUND: High prevalence rates of premature CAD have been reported in migrant Asian Indians. There are very few studies on CAD in native Indians living in the Indian subcontinent. METHODS: The Chennai Urban Population Study (CUPS) is an epidemiological study involving two residential areas in Chennai in South India. Of the total of 1,399 eligible subjects (age > or =20 years), 1,262 (90.2%) participated in the study. All the study subjects underwent a glucose tolerance test and were categorized as having normal glucose tolerance (NGT), impaired glucose tolerance (IGT) or diabetes. Twelve-lead electrocardiogram (ECG) was performed in 1,175 individuals (84%). Coronary artery disease was diagnosed based on previous medical history or Minnesota coding of ECGs. RESULTS: The overall prevalence rate of CAD is 11.0% (age standardized, 9.0%). The prevalence rates of CAD were 9.1%, 14.9% and 21.4% in those with NGT, IGT and diabetes, respectively. Prevalence of CAD increased with an increase in total cholesterol (trend chi-square: 26.2, p < 0.001), low-density lipoprotein (LDL) cholesterol (trend chi-square: 24.5, p < 0.001), triglycerides (trend chi-square: 9.96, p = 0.002) and total cholesterol/high-density lipoprotein ratio (trend chi-square: 6.14, p = 0.0132). Multiple logistic regression analysis identified age (odds ratio [OR]: 1.05, p < 0.001) and LDL cholesterol (OR: 1.009, p = 0.051) as the risk factors for CAD. CONCLUSIONS: The prevalence of CAD is rising rapidly in urban India. Lifestyle changes and aggressive control of risk factors are urgently needed to reverse this trend.
The insertion site polymorphism of the copia, mdg1, mdg3, gypsy, and P transposable elements was analysed by in situ hybridization to the polytene chromosomes in genomes of males from a natural population of Drosophila melanogaster. Parameters of various theoretical models of the population biology of transposable elements were estimated from our data, and different hypotheses explaining TE copy number containment were tested. The copia, mdg1 and gypsy elements show evidence for a deficiency of insertions on the X chromosomes, a result consistent with selection against the mutational effects of insertions. On the contrary, mdg3 and P copy numbers fit a neutral model with a balance between regulated transposition and excisions. There is no strong evidence of a systematic accumulation of elements in the distal and proximal regions of the chromosomes where crossing over and ectopic exchanges are reduced. For all chromosome arms but 3L, however, the TE site density increases from the proximal to the distal parts of the chromosomes (the centromeric regions were excluded in this analysis) with sometimes a sharp decrease in density at the extreme tip, following in part the exchange coefficient. The way the copy number of TEs is contained in genomes depends thus on the element considered, and on various forces acting simultaneously, indicating that models of TE dynamics should include details of each element.
Host snail demography and trematode parasitism were followed for one host generation in a shallow brackish lagoon of the western Baltic Sea. In addition, a laboratory experiment was simultaneously conducted to quantify the effects of parasitic infection on host fecundity. Hydrobia ventrosa of the cohort of 1996 had a maximum life-span of up to 2 years and reproduced between May and November of their second calendar year in 1997. Snails died after reproduction. The first trematode infections appeared in May 1997 when the snails started to mature. Total trematode prevalence peaked in summer and declined during winter to the lowest level in early spring 1998. Eight taxa of larval trematodes were found. Egg production of females with trematode infections was significantly reduced. Among females with pre-patent infections, about 20% were still able to produce eggs. Among females with patent infections merely 9% could lay eggs, compared to an average of about 51% in uninfected females. Taking into account a summer prevalence of about 25%, parasitic infections caused an overall reduction in egg production of the snail host population of about 15%. The reduction in host fecundity as a result of larval trematode infection did not measurably affect the population dynamics of H. ventrosa, because other environmental factors, especially winter severity and available food supply, were concluded to be much more relevant.
Meiotic metaphases II from archival slides were studied of male house mice caught in a hybrid zone between a population monomorphic for nine centric fusions (2n = 22) and a population with the standard karyotype (2n = 40), near Rome. The frequency of aneuploidy increases, up to 50%, with increasing number of heterozygous centric fusions (1-4).
The fate of advantageous alleles affecting intrinsic growth rate, carrying capacity or intra-specific competitive ability was examined in a partially inbreeding population. Generally, inbreeding had an effect on the evolution of advantageous alleles affecting population ecological characteristics. For example, in a specific underdominant case the number of stable internal equilibria decreased from two to one with only a slight degree of inbreeding. Equilibrium frequencies of stable internal equilibria and stability of fixation equilibria were also affected by the degree of inbreeding. For strictly advantageous alleles, inbreeding had the same qualitative effect on the fixation probability and mean fixation time as predicted in simpler selection models.
Restriction site mapping of mitochondrial DNA with 23 restriction endonucleases was used to examine the genetic and phylogenetic relationships of populations of D. silvestris and D. heteroneura from the island of Hawaii. Two morphological races of D. silvestris are known on the island of Hawaii. One has three bristle rows on the tibia of the foreleg and is found on the east side of the island. The other is found on the west side of the island and has the ancestral bristle row character of two rows on the tibia of the foreleg. All D. heteroneura have the ancestral bristle row character state. We demonstrate that mtDNA restriction site analysis can also differentiate the two D. silvestris races, and that the two bristle row D. silvestris are more closely related to D. heteroneura than they are to their three bristle row conspecifics using both distance and character state analysis. Our study (which uses six base recognition restriction endonucleases) is not sensitive enough to determine the phylogenetic relationships of populations within either of the D. silvestris lineages.
A hypervariable simple sequence locus and mitochondrial D-loop sequences were used to analyse genetically a natural population of the larger mouse-eared bat Myotis myotis in southern Bavaria. Tests for population subdivision and direct observations suggest that females return to their natal sites, while males disperse. The males present in female nursery colonies are not related to the females. Paternity assessment for 46 offspring from a particular nursery colony showed that there are no males that monopolize the reproduction, and that the resident males in the colony had only a small mating success. Instead, the results suggest that females actively seek matings outside their colony. Most interestingly, it appears that a group of males about 16 km away from the nursery colony had a relatively high mating success and that this group of males may be related to the females of the nursery colonies. If this finding can be confirmed in a larger study, it may have important consequences for future conservation strategies.
Genetic studies have emphasized the contrast between North African and sub-Saharan populations, but the particular affinities of the North African mtDNA pool to that of Europe, the Near East, and sub-Saharan Africa have not previously been investigated. We have analysed 268 mtDNA control-region sequences from various Northwest African populations including several Senegalese groups and compared these with the mtDNA database. We have identified a few mitochondrial motifs that are geographically specific and likely predate the distribution and diversification of modern language families in North and West Africa. A certain mtDNA motif (16172C, 16219G), previously found in Algerian Berbers at high frequency, is apparently omnipresent in Northwest Africa and may reflect regional continuity of more than 20,000 years. The majority of the maternal ancestors of the Berbers must have come from Europe and the Near East since the Neolithic. The Mauritanians and West-Saharans, in contrast, bear substantial though not dominant mtDNA affinity with sub-Saharans.
PURPOSE: The aims of the EUREYE study are to evaluate the prevalence of age-related maculopathy (ARM), including macular degeneration (AMD), in elderly European populations, to investigate risk factors for ARM and AMD, especially solar radiation and diet, and to measure the impact of these conditions on vision-related quality of life. METHODS: A population-based cross-sectional study with retrospective and current exposure measurements. Risk factor assessment is via questionnaires (for lifestyle factors such as smoking and alcohol, dietary risk factors, outdoor exposure) and blood analysis. Participants are people aged 65 and over. The study is carried out in 7 centres with locations spanning north to south Europe. The main outcome measure is grading of fundus photographs (for stage and type of ARM, using the International ARM Epidemiological Study Group grading system).
AIMS: The aim was to quantify and characterize the incidence of fall injury events among middle-aged and older adults who require acute medical attention at Danish hospitals. METHODS: A one-year population surveillance study was carried out, based on the Danish National Hospital Register (DNHR), which covers all somatic hospital discharges and accident and emergency (A&E) services at hospitals in Denmark. RESULTS: During 1996 a total of 81,121 fall injury events were treated at A&E departments or resulted in admission to a somatic hospital department among Danes aged 45 years and over. Up to age 50 years the incidence rates of injurious fall events requiring medical attention were similar in men and women. At age 50 years, the incidence rates in women exceeded the rates in men and remained 1.2-1.8 times higher thereafter. After age 70 years, the rates increased exponentially in both sexes: from 27.4 and 49.3 per 1,000 person-years in men and women, respectively, to peaks of 112.8 and 170.8 per 1,000 person-years, respectively, at age 85 years and over. The proportion of falls occurring indoors and in institutional settings increased with advancing age. Compared with men, women had higher rates of fall-related contusions, distortions and fractures at all ages. CONCLUSIONS: Fall-prevention programmes should be directed towards the population aged 70 years and over, in particular towards women and hazards in residential environments. Our finding of an increasing incidence of injurious fall events among women around the time of the menopause raises the hypothesis that loss of oestrogen production plays a role in the aetiology of falls in women.
The authors' aim in this study was to explore the prevalence, symptomatology, and risk factors for peptic ulcer in a general adult population. Between December 1998 and June 2001, the authors surveyed a random sample (n=3,000) of the adult population (n=21,610) in two communities in northern Sweden using a validated questionnaire, the Abdominal Symptom Questionnaire (response rate=74%). A subsample (n=1,001) of the responders was randomly invited to undergo esophagogastroduodenoscopy and symptom assessment (response rate=73%). The prevalence of peptic ulcer was 4.1% (20 gastric ulcers and 21 duodenal ulcers). Nausea and gastroesophageal reflux were significant predictors of peptic ulcer disease, but epigastric pain/discomfort was not. Six persons with gastric ulcer and two persons with duodenal ulcer were asymptomatic. Eight subjects with duodenal ulcer (38%) lacked evidence of current Helicobacter pylori infection. Five (25%) of the gastric ulcers and four (19%) of the duodenal ulcers were idiopathic (no use of aspirin or nonsteroidal antiinflammatory drugs, no H. pylori infection). Smoking, aspirin use, and obesity were risk factors for gastric ulcer; smoking, low-dose (<or=160 mg) aspirin use, and H. pylori infection were risk factors for duodenal ulcer. Peptic ulcer disease often coexists with atypical symptoms or no symptoms at all, and idiopathic duodenal ulcer may be more common than anticipated.
UNLABELLED: We present Serial SimCoal, a program that models population genetic data from multiple time points, as with ancient DNA data. An extension of SIMCOAL, it also allows simultaneous modeling of complex demographic histories, and migration between multiple populations. Further, we incorporate a statistical package to calculate relevant summary statistics, which, for the first time allows users to investigate the statistical power provided by, conduct hypothesis-testing with, and explore sample size limitations of ancient DNA data. AVAILABILITY: Source code and Windows/Mac executables at http://www.stanford.edu/group/hadlylab/ssc.html CONTACT: senka@stanford.edu.
Drosophila mercatorum is a bisexual species, but certain strains are capable of parthenogenetic reproduction in the laboratory. We investigated the parthenogenetic capacity of the virgin daughters of females captured from a natural, bisexual population in Hawaii. An isozyme survey indicated the natural population is polymorphic at about 50% of its loci, and its individuals heterozygous at 18% of their loci. The predominant mode of parthogenesis in D. mercatorum causes homozygosity for all loci in a single generation. Despite this radical change in genetic state, 23% of the virgin female lines produced adult parthenogenetic progeny, and 16% produced parthenogenetic progeny themselves capable of parthenogenetic reproduction. The parthenogenetic rats as measured by the number of parthenogenetic progeny themselves capable of parthenogenesis divided by the number of eggs laid is arougn 10(-5) for the virgin female lines. We argue that one of the major reasons for this low rate is that very few of the impaternate zygotes have a genotype that can survive and reproduce under the genetic conditions imposed by parthenogenetic reproduction. This intense selective bottleneck can be passed in a single generation if enough unfertilized eggs are laid, and once passed is accompanied by a large (perhaps a thousandfold) increase in the rate of parthenogenesis and by modifications in many phenotypic traits such as morphology and behavior.
Properties of identity relation between genes are discussed, and a derivation of recurrent equations of identity coefficients in a random mating, diploid dioecious population is presented. Computations are run by repeated matrix multiplication. Results show that for effective population size (Ne) larger than 16 and no mutation, a given identity coefficient at any time t can be expressed approximately as a function of (1--f), (1--f)3 and (1--f)6, where f is the mean inbreeding coefficient at time t. Tables are presented, for small Ne values and extreme sex ratios, showing the pattern of change in the identity coefficients over time. The pattern of evolution of identity coefficients is also presented and discussed with respect to Neu, where u is the mutation rate. Applications of these results to the evolution of genetic variability within and between inbred lines are discussed.