Genetic drift with polygamy and arbitrary offspring distribution

The rate of genetic drift at an autosomal locus for a bisexual, diploid population of fixed size is studied. The generations are non-overlapping. The model encompasses a variety of mating systems, including random monogamy, random polygamy in one sex and random mating. The rate of drift is shown for several models to depend on the expected number of parents that two randomly selected individuals have in common. The male and female offspring are assigned to families in a fairly general way, which permits the study of a model in which each family has offspring of one sex only. The equation arising in this last case is identical to one of Jacquard for a system in which sib-mating is excluded.

Effective size of populations under selection.

Genetics ◽

10.1093/genetics/139.2.1013 ◽

1995 ◽

Vol 139 (2) ◽

pp. 1013-1030 ◽

Cited By ~ 3

Author(s):

E Santiago ◽

A Caballero

Keyword(s):

Random Mating ◽

Intraclass Correlation ◽

Cumulative Effect ◽

Prediction Equation ◽

Effective Size ◽

Gene Effects ◽

Male And Female ◽

Sib Mating ◽

Average Proportion

Abstract Equations to approximate the effective size (Ne) of populations under continued selection are obtained that include the possibility of partial full-sib mating and other systems such as assortative mating. The general equation for the case of equal number of sexes and constant number of breeding individuals (N) is Ne = 4N/[2(1 - alpha I) + (Sk2 + 4Q2C2) (1 + alpha I + 2 alpha O)], where Sk2 is the variance of family size due to sampling without selection, C2 is the variance of selective advantages among families (the squared coefficient of variation of the expected number of offspring per family), alpha I is the deviation from Hardy-Weinberg proportions, alpha O is the correlation between genes of male and female parents, and Q2 is the term accounting for the cumulative effect of selection on an inherited trait. This is obtained as Q = 2/[2 - G(1 + r)], where G is the remaining proportion of genetic variance in selected individuals and r is the correlation of the expected selective values of male and female parents. The method is also extended to the general case of different numbers of male and female parents. The predictive value of the formulae is tested under a model of truncation selection with the infinitesimal model of gene effects, where C2 and G are a function of the selection intensity, the heritability and the intraclass correlation of sibs. Under random mating r = alpha I = -1/(N - 1) and alpha O = 0. Under partial full-sib mating with an average proportion beta of full-sib matings per generation, r approximately beta and alpha O approximately alpha I approximately beta/(4 - 3 beta). The prediction equation is compared to other approximations based on the long-term contributions of ancestors to descendants. Finally, based on the approach followed, a system of mating (compensatory mating) is proposed to reduce rates of inbreeding without loss of response in selection programs in which selected individuals from the largest families are mated to those from the smallest families.

Genetic drift with polygamy and arbitrary offspring distribution

Advances in Applied Probability ◽

10.2307/1426196 ◽

1974 ◽

Vol 6 (1) ◽

pp. 3-4

Author(s):

C. Cannings

Keyword(s):

Simple Model ◽

Genetic Drift ◽

Overlapping Generations ◽

Fixed Size ◽

Diploid Population ◽

Offspring Distribution

Wright (1931) introduced a simple model for a bisexual, diploid population of fixed size and with non-overlapping generations. With N1 males and N2 females, the rate of drift was λ0 = 1 – (N/8N1N2) where N = N1 + N2.

Genetic drift with polygamy and arbitrary offspring distribution

Advances in Applied Probability ◽

10.1017/s0001867800039604 ◽

1974 ◽

Vol 6 (01) ◽

pp. 3-4

Author(s):

C. Cannings

Keyword(s):

Simple Model ◽

Genetic Drift ◽

Overlapping Generations ◽

Fixed Size ◽

Diploid Population ◽

Offspring Distribution

Wright (1931) introduced a simple model for a bisexual, diploid population of fixed size and with non-overlapping generations. WithN1males andN2females, the rate of drift wasλ0= 1 – (N/8N1N2) whereN=N1+N2.

Placental treatment improves cardiac tolerance to ischemia/reperfusion insult in adult male and female offspring exposed to prenatal hypoxia

Pharmacological Research ◽

10.1016/j.phrs.2021.105461 ◽

2021 ◽

Vol 165 ◽

pp. 105461

Author(s):

Nataliia Hula ◽

Floor Spaans ◽

Jennie Vu ◽

Anita Quon ◽

Raven Kirschenman ◽

...

Keyword(s):

Adult Male ◽

Ischemia Reperfusion ◽

Female Offspring ◽

Prenatal Hypoxia ◽

Male And Female

Average Number of Nucleotide Differences in a Sample From a Single Subpopulation: A Test for Population Subdivision

Genetics ◽

10.1093/genetics/117.1.149 ◽

1987 ◽

Vol 117 (1) ◽

pp. 149-153

Author(s):

Curtis Strobeck

Keyword(s):

Monte Carlo Simulation ◽

Population Structure ◽

Random Mating ◽

Population Subdivision ◽

Expected Number ◽

Migration Rates ◽

Mating Population ◽

Unbiased Estimates ◽

Increasing Function ◽

Stepping Stone Model

ABSTRACT Unbiased estimates of θ = 4Nµ in a random mating population can be based on either the number of alleles or the average number of nucleotide differences in a sample. However, if there is population structure and the sample is drawn from a single subpopulation, these two estimates of θ behave differently. The expected number of alleles in a sample is an increasing function of the migration rates, whereas the expected average number of nucleotide differences is shown to be independent of the migration rates and equal to 4N Tµ for a general model of population structure which includes both the island model and the circular stepping-stone model. This contrast in the behavior of these two estimates of θ is used as the basis of a test for population subdivision. Using a Monte-Carlo simulation developed so that independent samples from a single subpopulation could be obtained quickly, this test is shown to be a useful method to determine if there is population subdivision.

Perinatal SSRIs, maternal stress, and their effects on social behaviors in male and female offspring

Toxicology Letters ◽

10.1016/j.toxlet.2017.07.185 ◽

2017 ◽

Vol 280 ◽

pp. S72

Author(s):

Jodi Pawluski

Keyword(s):

Maternal Stress ◽

Social Behaviors ◽

Female Offspring ◽

Male And Female

PRE-MATERNAL ISOLATION EFFECTS ON BEHAVIOUR AND ENDOCRINE FUNCTION OF OFFSPRING

Acta Endocrinologica ◽

10.1530/acta.0.0620367 ◽

1969 ◽

Vol 62 (2) ◽

pp. 367-384 ◽

Cited By ~ 2

Author(s):

A. M. Sackler ◽

A. S. Weltman ◽

R. Schwartz ◽

P. Steinglass

Keyword(s):

Locomotor Activity ◽

Growth Rates ◽

Female Offspring ◽

The Body ◽

Endocrine Function ◽

Male And Female ◽

Isolation Stress ◽

Developmental Growth ◽

Body Weights ◽

And Control

ABSTRACT This report was designed to determine combined effects of maternal endocrine imbalances and abnormal behaviour due to prolonged isolation stress of female mice on the behaviour, developmental growth rate and endocrine function of their offspring. Sixty female albino mice averaging 19 g were divided equally into isolated and control groups. The isolated females were housed singly; control females were maintained in groups of 2 mice per cage. After observation of behavioural and physiological effects characteristic of isolation stress in the test mice, all isolated and control mice were mated after a 6½ month experimental, isolation period. No differences were observed in fertility and fecundity of the two groups of mothers. Analyses of developmental growth rates of the litters of the isolated versus control mothers showed significantly lower body weights in the test offspring at 3 and 4 weeks of age. The body weights of the female offspring remained significantly lower from the 4th to 11th weeks. The effects on the body weights of the male offspring declined and were no longer statistically significant at the 5th to 11 weeks. Locomotor activity at 4½ and 8 weeks of age was markedly or significantly higher in the male and female mice from isolated mothers. Tail-blood samples taken prior to autopsy at 5 and 11 weeks of age revealed significant decreases in the total leukocyte and eosinophil counts of both sexes. At the two ages, the absolute and relative spleen and thymus weights of the male and female offspring were markedly and/or significantly lower than the values observed in counterpart young from control females. Significant decreases were also observed in the absolute gonadal organ weights of both sexes at 11 weeks of age. The various data indicated inhibited growth rates, heightened locomotor activity and evasiveness, as well as evidence of increased adrenocortical function in the offspring from test mothers. The gonadal weight decreases suggested retarded gonadal development. Further studies using split-litter techniques are required to differentiate the effects of prenatal endocrine imbalances versus postnatal maternal influence (i. e., nursing care) on the offspring.

Deviation from Hardy–Weinberg proportions in finite populations

Genetics Research ◽

10.1017/s0016672300034224 ◽

1996 ◽

Vol 68 (3) ◽

pp. 249-257 ◽

Cited By ~ 13

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.

Effects of Maternal Hyperglycemia Associated with Snack Intake on Male and Female Offspring High-Fat Diet Preference on Infancy

Metabolism ◽

10.1016/j.metabol.2020.154635 ◽

2021 ◽

Vol 116 ◽

pp. 154635

Author(s):

Gustavo Venâncio da Silva ◽

Marina Galleazzo Martins ◽

Giovana Pereira de Oliveira ◽

Alessandra Gonçalves Cruz ◽

Larissa Pereira Rodrigues ◽

...

Keyword(s):

High Fat Diet ◽

Female Offspring ◽

High Fat ◽

Male And Female ◽

Maternal Hyperglycemia ◽

Diet Preference