Age-related allozymic variation in the cyprinid fish Alburnus alburnus

1983 ◽  
Vol 61 (12) ◽  
pp. 2844-2848 ◽  
Author(s):  
Paul Handford
Keyword(s):  
Random Mating ◽  
Cyprinid Fish ◽  
Size Class ◽  
Water Soluble ◽  
Single Locus ◽  
Allozymic Variation ◽  
Genotype Frequencies ◽  
Age Related ◽  
Weinberg Expectation

A polymorphism in water-soluble muscle esterases in the freshwater cyprinid fish Alburnus alburnus, the bleak, is described. The variation may be attributed to three codominant alleles at a single locus. Strong distortions from Hardy–Weinberg expectation are noted in samples from all length groups of fish at all times of the year. All homozygotes and one heterozygote are generally in deficit, while the two common heterozygotes are present in excess. Analysis of the genotype frequencies on a basis of random mating indicates that the polymorphism is stable and close to equilibrium. There are significant associations between size class and the frequencies of alleles 1 and 2 and genotype 33.

scholarly journals The general relationship between average effect and average excess

1987 ◽  
Vol 49 (1) ◽  
pp. 69-70 ◽  
Author(s):  
Alan R. Templeton
Keyword(s):  
Analytical Solution ◽  
Random Mating ◽  
General Relationship ◽  
Single Locus ◽  
Average Effect ◽  
Matrix Notation ◽  
Weinberg Equilibrium ◽  
General Analytical Solution ◽  
Genotype Frequencies ◽  
Hardy Weinberg Equilibrium

SummaryThe average effect and average excess both measure the phenotypic effects of gametes in a population. A matrix notation is introduced that provides a general analytical solution for the average effects at a single locus with k alleles that can be solved for any population regardless of its genotype frequencies. This same notation also provides an easy way of deriving and generalizing to k alleles the well-known relationships between average effects and average excesses that exist under random-mating and regular deviations from Hardy–Weinberg equilibrium due to inbreeding.

Patterns of variation in a number of genetic systems in Maniola jurtina: the boundary region

1973 ◽  
Vol 183 (1072) ◽  
pp. 265-284 ◽  
Keyword(s):  
Hind Wing ◽  
Distribution Patterns ◽  
Boundary Region ◽  
Water Soluble ◽  
Single Locus ◽  
Geographical Patterns ◽  
Genotype Frequencies ◽  
Spot Number ◽  
Silent Allele ◽  
Maniola Jurtina

Samples of the butterfly Maniola jurtina have been collected from a number of sites along an east–west transect in southwest England. A number of individuals from most of these samples were analysed for variation in water-soluble esterases by electrophoresis on acrylamide gels. The females showed two polymorphic systems; the first, designated Es–A, has variation with the suggested basis of three alleles at a single locus: Es–A 1 , Es–A 2 and Es–A N the last allele being a null or silent allele, i. e. producing no detectable enzyme. The second system, termed Es–B, has a total of six phenotypes and these have been explained as the genotypes given by three alleles at a single locus: Es–B 0 , Es–B 1 and Es–B 2 all of which produce a functioning enzyme. The males generally gave poor gel preparations, and they seemed to show no variation: all had the Es–A 1 band, and in the Es–B region, bands, when present, were in the Es–B 1 position. The Es–A and Es–B systems appeared to be independent of one another. There is no association between the esterase morphology of a given individual and its hind-wing spotting pattern. The geographical patterns in gene and genotype frequencies of both enzyme systems are described, and these patterns are compared with those shown by spot number and spot position (costality index). The distribution patterns shown by the esterase morphs would seem to emphasize that the boundary region is a zone of ‘genetic disturbance’. The biological meaning of these phenomena is discussed.

scholarly journals Deviation from Hardy–Weinberg proportions in finite populations

1996 ◽  
Vol 68 (3) ◽  
pp. 249-257 ◽  
Author(s):  
Jinliang Wang
Keyword(s):  
Sampling Error ◽  
Random Mating ◽  
Random Selection ◽  
Stochastic Simulations ◽  
Gene Frequencies ◽  
Dioecious Species ◽  
Male And Female ◽  
Census Size ◽  
Genotype Frequencies ◽  
Gene Frequency Difference

SummaryFor a finite diploid population with no mutation, migration and selection, equations for the deviation of observed genotype frequencies from Hardy–Weinberg proportions are derived in this paper for monoecious species and for autosomal and sex-linked loci in dioecious species. It is shown that the genotype frequency deviation in finite random-mating populations results from the difference between the gene frequencies of male and female gametes, which is determined by two independent causes: the gene frequency difference between male and female parents and the sampling error due to the finite number of offspring. Previous studies have considered only one of the causes and the equations derived by previous authors are applicable only in the special case of random selection. The general equations derived here for both causes incorporate the variances and covariances of family size and thus they reduce to previous equations for random selection. Stochastic simulations are run to check the predictions from different formulae. Non-random mating and variation in census size are considered and the applications of the derived formulae are exemplified.

scholarly journals Kidney aging.Geriatric view

2021 ◽  
pp. 76-81
Author(s):  
L. I. Merkusheva ◽  
N. K. Runikhina ◽  
O. N. Tkacheva
Keyword(s):  
Chronic Kidney Disease ◽  
Renal Function ◽  
Kidney Disease ◽  
Structural Changes ◽  
Water Soluble ◽  
Older Age ◽  
Sodium Reabsorption ◽  
Tubular Atrophy ◽  
Age Related ◽  
Population Demographic

Individuals age >65 years old are the fastest expanding population demographic throughout the developed world. Consequently, more aged patients than before are receiving diagnoses of impaired renal function and nephrosclerosis. In this review, we examine these features of the aged kidney and explore the various validated and putative pathways contributing to the changes observed with aging. Senescence or normal physiologic aging portrays the expected age-related changes in the kidney as compared to chronic kidney disease (CKD) in some individuals. The microanatomical structural changes of the kidney with older age include a decreased number of functional glomeruli from an increased prevalence of nephrosclerosis (arteriosclerosis, glomerulosclerosis, and tubular atrophy with interstitialfibrosis), and to some extent, compensatory hypertrophy of remaining nephrons. Among the macroanatomical structural changes, older age associates with smaller cortical volume. There is reason to be concerned that the elderly are being misdiagnosed with CKD. In addition to the structural changes in the kidney associated with aging, physiological changes in renal function are also found in older adults, such as decreased glomerular filtration rate, vascular dysautonomia, altered tubular handling of creatinine, reduction in sodium reabsorption and potassium secretion, and diminished renal reserve. These alterations make aged individuals susceptible to the development of clinical conditions in response to usual stimuli that would otherwise be compensated for in younger individuals, including acute kidney injury, volume depletion and overload, disorders of serum sodium and potassium concentration, and toxic reactions to water -soluble drugs excreted by the kidneys. Additionally, the preservation with aging of a normal urinalysis, normal serum urea and creatinine values, erythropoietin synthesis, and normal phosphorus, calcium and magnesium tubular handling distinguishes decreased GFR due to normal aging from that due to chronic kidney disease.

scholarly journals Polymorphisms of pleiotropic genes ABCC11 and ACE in Abkhazians and the longevity phenomenon

2019 ◽  
pp. 29-36
Author(s):  
С.В. Макаров ◽  
М.К. Карапетян ◽  
К.Б. Квеквескири ◽  
В.А. Спицын
Keyword(s):  
Multiple Drug Resistance ◽  
Control Group ◽  
Multiple Drug ◽  
Ace Gene ◽  
Caucasus Region ◽  
Gene Insertion ◽  
Vital Functions ◽  
Genotype Frequencies ◽  
Age Related ◽  
And Control

Изучение наследственных факторов в детерминации долголетия представляется весьма актуальным в связи с ростом средней продолжительности жизни, поиском возможностей продления «здорового» периода в позднем отногенезе. Феномен высокой продолжительности жизни всегда вызывал особый интерес исследователей, а его изучение представляется наиболее перспективным в популяциях с достаточно большой долей долгожителей. С давних времен известны случаи ярко выраженного активного долголетия в регионе Кавказа. У долгожителей Абхазии темпы соматического развития, уровень обменных процессов и меньшая интенсивность возрастной инволюции скелета указывали на относительно «здоровый» тип старения. Среди генетических факторов, которые потенциально могли бы играть важную роль в достижении долголетия, особенно перспективным представляется изучение плейотропных генов, действие которых проявляется во множественных эффектах и обладающих высокой функциональной значимостью. Среди них особый интерес представляют те, которые определяют эффективность функционирования сердечно-сосудистой системы, а также особенности, влияющие на темп созревания и старения организма. К числу таких генов можно отнести ген ангиотензин-превращающего фермента (ACE) и ген множественной лекарственной устойчивости (ABCC11). Целью исследования был поиск закономерностей в характере распределения полиморфных вариантов плеойтропных генов ABCC11 и ACE в популяции абхазов в связи с возрастом обследуемых и наличием долгожителей в выборке. В качестве материала исследования были собраны образцы клеток буккального эпителия от коренных жителей Абхазии, подразделенных на две группы: старшего возраста (75-101 год, 79 человек) и контрольную ( 97 индивидов в возрасте от 16 до 33 лет ). Анализ распределений частот генотипов и аллелей полиморфизма 538G>A (rs17822931) гена ABCC11 показал, что группы старшего возраста и контроля очень сходны между собой и достоверные различия между выборками отсутствуют. Генотипирование по инсерционно-делеционному полиморфизму гена ACE (rs1799752) осуществлялось методом ПЦР-ПДАФ. Для контрольной группы абхазов установлены следующие частоты генотипов: II = 0,186; ID = 0,412; DD = 0,402, частоты аллелей I и D оказались равны 0,392 и 0,608 соответственно. Группа старшего возраста по частотам генотипов существенно не отличалась от контроля, генотипы II/ID/DD были распределены в соотношении 0,088/0,380/0,532, а частоты аллелей I и D оказались равны 0,278 и 0,722 соответственно. В результате исследования выявлено, что частота аллеля делеции по инсерционно-делеционному полиморфизму в гене ACE в старшей возрастной группе абхазов достоверно повышена по сравнению с контрольной группой. The study of the phenomenon of longevity is the most promising in populations with a fairly large proportion of centenarians. Since old times cases of pronounced active longevity have been widely known in the Caucasus region. The complexity of age-related processes of aging assumes the involvement of multiple complex factors that have affect on life expectancy. Therefore the study of the pleiotropic genes with their multiple effects and functions could be helpful in that case. The angiotensin I-converting enzyme (ACE) gene and the multiple drug resistance gene ( ABCC11) are of great interest because of their high importance for essential vital functions. The aim of the study was the search for correlations in the frequencies distribution of polymorphic variants of pleoitropic genes ABCC11 and ACE in the population of Abkhazians with the longevity. The material included the DNA samples from indigenous residents of Abkhazia. They were divided into two groups: older age (N = 79) and control (N = 97). The differences in the frequencies distribution of 538G>A genotypes and alleles of the gene ABCC11 in the older group and control were not significant. ACE gene insertion-deletion polymorphism ( rs1799752) genotyping was performed by PCR-AFLP. The genotype frequencies were : II = 0.186; ID = 0.412; DD = 0.402, allele frequencies I and D were equal to 0.392 and 0.608 for the control group of Abkhazians. The older group did not differ significantly from the control in genotype frequencies, the ratio for II/ID/DD genotypes were as 0.088/0.380/0.532, and the frequencies of alleles I and D corresponded to 0.278 and 0.722. The obtained results revealed that the ACE gene deletion allele frequency was significantly increased in the older group of Abkhazians.

Genetics of Cronartium ribicola. III. Mating System

1996 ◽  
Vol 74 (11) ◽  
pp. 1852-1859 ◽  
Author(s):  
Matthew A. Gitzendanner ◽  
Gayle E. Dupper ◽  
Eleanor E. White ◽  
Brett M. Foord ◽  
Paul D. Hodgskiss ◽  
...  
Keyword(s):  
Mating System ◽  
Genetic Recombination ◽  
Random Mating ◽  
Cronartium Ribicola ◽  
White Pine Blister Rust ◽  
Mendelian Segregation ◽  
Weinberg Equilibrium ◽  
Forest Pathogen ◽  
Genotype Frequencies ◽  
Hardy Weinberg Equilibrium

Lack of genetic markers has hindered the study of the mating system of Cronartium ribicola, an exotic forest pathogen Meeting natural and cultivated white pines throughout North America. Isozymes, randomly amplified polymorphic DNA (RAPDs), and restriction length polymorphisms (RFLPs) were used to study the mating system of this rust. Heterozygosity (outcrossing) in diploid telia was demonstrated by analysis of cultures derived from the meiotic products (basidiospores) of individual telia. Families of basidiospores cultured from single telia were used to test for Mendelian segregation and for conformance of loci to Hardy–Weinberg equilibrium. A total of 18 polymorphic loci were identified with the three marker systems. All except for three RAPD loci showed Mendelian segregation in the single-telium families. To quantify the level of outcrossing, gene and genotype frequencies were calculated for families from a single population. Up to 24 families were surveyed with isozymes, 14 with RAPDs, and 18 with RFLPs. Except for one isozyme locus (MPI) in one sample, all 14 loci tested with these families were in Hardy–Weinberg equilibrium, indicating random mating. Further studies, with a different sample from the same population, showed all three isozyme loci to be in Hardy–Weinberg equilibrium. The three marker systems were consistent as to the amount of variation detected. Resistance selection and breeding programs must consider the implications of genetic recombination that outcrossing affords the rust. Keywords: isozymes, RAPDs, RFLPs, Hardy–Weinberg equilibrium, white pine blister rust.

The Significance of Persistent Vocalisation By the Spring Peeper, Pseudacris Crucifer (Anura: Hylidae)

Behaviour ◽  
1989 ◽  
Vol 108 (3-4) ◽  
pp. 197-208 ◽  
Author(s):  
David V. Lykens ◽  
Don C. Forester ◽  
W. Keith Harrison
Keyword(s):  
Body Size ◽  
Mating Success ◽  
Significant Variation ◽  
Random Mating ◽  
Weather Conditions ◽  
Size Class ◽  
Reproductive Season ◽  
Mating Activity ◽  
Good Physical Condition ◽  
Pseudacris Crucifer

Abstract1. Male spring peepers exhibit individual variation in calling persistence within as well as between nights. 2. Weather conditions influence nightly variation in calling persistence throughout the reproductive season, but there is a pronounced decrease in calling persistence late in the season which appears to be independent of climate. 3. In four speaker experiments simulating males calling 20, 40, 60, and 80% of the time, there is a positive correlation between time spent calling and mating success. 4. On nights when there is significant variation in calling persistence, females likely respond to those males which are most persistent (i.e. , produce the most conspicuous calls). 5. In four speaker experiments simulating males calling 80, 85, 90 and 95% of the time, mating success is random, suggesting that during periods of peak mating activity the importance of female choice is diminished. 6. Calling persistence is not correlated with body size, therefore males of any age or size class have an opportunity to experience mating success. 7. Anuran vocalization is known to be energetically expensive, and persistent callers (regardless of their size) are likely in good physical condition. 8. We suggest that by responding (either actively or passively) to the most conspicuous calls, females convey to their offspring an advantage above and beyond that accrued by random mating.

Allozyme Genotype and Differential Resistance to Mercury Pollution in the Caddisfly, Nectopsyche albida. II. Multilocus Genotypes

1992 ◽  
Vol 49 (1) ◽  
pp. 147-149 ◽  
Author(s):  
Michael J. Benton ◽  
Sheldon I. Guttman
Keyword(s):  
Survival Time ◽  
Inorganic Mercury ◽  
Differential Resistance ◽  
Single Locus ◽  
Multilocus Genotype ◽  
Starch Gel Electrophoresis ◽  
Time To Death ◽  
Multilocus Genotypes ◽  
Genotype Frequencies ◽  
Starch Gel

While a number of papers document that sensitivity to pollution is correlated with single-locus genotype, only one has addressed associations with multilocus complexes. We exposed larval caddisflies, Nectopsyche albida, to inorganic mercury and recorded individual times to death, genetically characterized each individual at six polymorphic loci by starch gel electrophoresis, and tested the effects of multilocus genotype on time to death. Two two-locus complexes and two three-locus complexes were significantly correlated with survival time. This supports earlier studies that monitoring multilocus and single-locus genotype frequencies may be useful in detecting and measuring environmental impacts; however, we disagree that variation in survival time among genotypes per se supports selectionist theory, because no heritability of resistance has been demonstrated. We also disagree that enzyme systems not exhibiting such variation are nonadaptive and discuss how the elimination of sensitive multilocus genotypes may hinder population persistence.

scholarly journals A test for Hardy-Weinberg equilibrium on the X chromosome for sex-biased admixed populations

2019 ◽  
Author(s):  
Daniel Backenroth ◽  
Shai Carmi
Keyword(s):  
X Chromosome ◽  
Random Mating ◽  
Allele Frequencies ◽  
Ratio Test ◽  
Weinberg Equilibrium ◽  
Genotype Frequencies ◽  
Genome Wide ◽  
Control Step ◽  
Hardy Weinberg Equilibrium ◽  
Males And Females

AbstractGenome-wide scans for deviations from Hardy-Weinberg equilibrium (HWE) are commonly applied to detect genotyping errors. In contrast to the autosomes, genotype frequencies on the X chromosome do not reach HWE within a single generation. Instead, if allele frequencies in males and females initially differ, they oscillate for a few generations towards equilibrium. Several populations world-wide have experienced recent sex-biased admixture, namely, their male and female founders differed in ancestry and thus in allele frequencies. Sex-biased admixture makes testing for HWE difficult on X, because deviations are naturally expected, even under random mating post-admixture and error-free genotyping. In this paper, we develop a likelihood ratio test and a χ2 test that detect deviations from HWE on X while allowing for natural deviations due to sex-biased admixture. We demonstrate by simulations that our tests are powerful for detecting deviations due to non-random mating, while at the same time they do not reject the null under historical sex-biased admixture and random mating thereafter. We also demonstrate that when applied to 1000 Genomes project populations (e.g., as a quality control step), our tests reject fewer SNPs (among those showing frequency differences between the sexes) than other tests.

scholarly journals Evaluating pediatric and adult simulated fluids solubility: Abraham solvation parameters and multivariate analysis

2021 ◽  
Author(s):  
Mariana Guimarães ◽  
Martin Kuentz ◽  
Maria Vertzoni ◽  
Nikoletta Fotaki
Keyword(s):  
Water Soluble ◽  
Drug Solubility ◽  
Least Squares Regression ◽  
Biorelevant Media ◽  
Discrimination Ability ◽  
Age Related ◽  
Solvation Parameters ◽  
Solubility Ratio ◽  
Age Related Changes

Abstract Purpose To understand drug solubilization as a function of age and identify drugs at risk of altered drug solubility in pediatric patients. To assess the discrimination ability of the Abraham solvation parameters and age-related changes in simulated media composition to predict in vitro drug solubility differences between pediatric and adult gastrointestinal conditions by multivariate data analysis. Methods Differences between drug solubility in pediatric and adult biorelevant media were expressed as a % pediatric-to-adult ratio [Sp/Sa (%)]. Solubility ratios of fourteen poorly water-soluble drugs (2 amphoteric; 4 weak acids; 4 weak bases; 4 neutral compounds) were used in the analysis. Partial Least Squares Regression was based on Abraham solvation parameters and age-related changes in simulated gastrointestinal fluids, as well as their interactions, to predict the pediatric-to-adult solubility ratio. Results The use of Abraham solvation parameters was useful as a theory-informed set of molecular predictors of drug solubility changes between pediatric and adult simulated gastrointestinal fluids. Our findings suggest that the molecular solvation environment in the fasted gastric state was similar in the pediatric age-groups studied, which led to fewer differences in the pediatric-to-adult solubility ratio. In the intestinal fasted and fed state, there was a high relative contribution of the physiologically relevant surfactants to the alteration of drug solubility in the pediatric simulated conditions compared to the adult ones, which confirms the importance of an age-appropriate composition in biorelevant media. Conclusion Statistical models based on Abraham solvation parameters were applied mostly to better understand drug solubility differences in adult and pediatric biorelevant media.

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