The Demopaedia team will be present at the next International Population Conference in Busan.
If you attend the conference, please, come to our oral communication which will be held on Tuesday August 27, from 15:30 to 17:00 (Bexco, room 213). The new Korean dictionary will also be presented in a side meeting organized by the Planned Population Federation of Korea (PPFK) on "Population Issues & Official development assistance" (open to all) at 19:00 (Bexco, room 110).

91

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The harmonization of all the second editions of the Multilingual Demographic Dictionary is an ongoing process. Please consult the discussion area of this page for further comments.


Go to: Introduction to Demopædia | Instructions on use | Downloads
Chapters: Preface | 1. General concepts | 2. The treatment and processing of population statistics | 3. Distribution and classification of the population | 4. Mortality and morbidity | 5. Nuptiality | 6. Fertility | 7. Population growth and replacement | 8. Spatial mobility | 9. Economic and social aspects of demography
Pages: 10 | 11 | 12 | 13 | 14 | 15 | 16 | 20 | 21 | 22 | 23 | 30 | 31 | 32 | 33 | 34 | 35 | 40 | 41 | 42 | 43 | 50 | 51 | 52 | 60 | 61 | 62 | 63 | 70 | 71 | 72 | 73 | 80 | 81 | 90 | 91 | 92 | 93
Index: Global Index | Index of chapter 1 | Index of chapter 2 | Index of chapter 3 | Index of chapter 4 | Index of chapter 5 | Index of chapter 6 | Index of chapter 7 | Index of chapter 8 | Index of chapter 9


910

In eugenics 1, a discipline which seeks to improve the quality of the population, attention is directed primarily to the role of heredity 2, the transmission of hereditary characteristics 3, such as the color of the eyes, from generation to generation. Acquired characteristics 4 are not so transmitted. A lethal characteristic 5 generally brings about the early death of the foetus.

  • 1. Eugenics, n. - eugenic, adj. - eugenist, n.: a specialist in eugenics.
  • 2. Heredity, n. - hereditary, adj.

911

The transmission of hereditary characteristics operates through genes 1 which are transmitted to children by their parents. Genetics 2 is the science concerned with the transmission and effects of hereditary factors. The genes are carried by chromosomes 3 which are long filaments of DNA (deoxyribonucleic acid) located in the cell’s nucleus. The position of a gene on a chromosome is called its locus 4. Genes occupying the same locus affect the same characteristic, although they do so in various ways which correspond to various alleles 5 of the gene in this locus. The new cell formed by the union of two sexual cells or gametes 6 during the process of conception (602-1) is called a zygote 7.

  • 1. All of the genes carried by an individual are collectively called his or her genetic endowment.
  • 2. Genetics, n. - genetic, adj. - geneticist, n.: a specialist in genetics.

912

The set of two genes of an individual at the same locus is called a genotype 1; the genotype is said to be homozygous 2 if the alleles are identical at a given locus; it is said to be heterozygous 3 in the opposite case. The phenotype 4 consists in the observable characteristics as determined by the genotype and the environment. If an heterozygous individual (AA’) cannot be distinguished from an homozygous individual (AA), the allele A is said to be dominant 5 over allele A’, and A’ is said to be recessive 6. Genes are subject to sudden and apparently random changes, called mutations 7. Panmixia 8 or random mating 8 insures uniform distribution of genes within populations.

  • 7. Mutation, n. - mutant, adj. or n.

913

A distinction is frequently made in eugenic policy between positive eugenics 1, aimed at increasing the number of persons believed to have desirable characteristics, and negative eugenics 2 aimed at restricting the reproduction of persons expected to transmit undesirable characteristics or hereditary defects 3. Much attention has been given to the discussion of eugenic sterilization 4, i.e., the sterilization of persons likely to transmit undesirable characteristics to their descendants. Objections to this measure have been raised on moral grounds and also because of its relatively low efficiency in reducing the frequency of recessive genes (912-6). Among the measures proposed, pre-marital examination 5 may be mentioned; this is designed to give couples intending to marry information about the probable quality of their offspring, so that prospective partners to dysgenic marriages 6, i.e., those likely to produce defectives, may be warned.

914

The probability that an individual of reproductive age will have a given number of offspring who also attain reproductive age may depend on his genotype (912-1). This differential reproduction is called selection 1. The selective value 2 or fitness value 2 of a genotype is the relative number of children of individuals with the genotype who survive to reproductive age. The mean selective value 3 or fitness 3 of a population is equal to the average of the selective values for the genotypes of its members. The genetic load 4 of the population is the relative decline in the mean value of fitness resulting from the presence of different genotypes with varying fitness values. Random fluctuation of the frequency with which a specific gene is found in different generations of a population is called the genetic drift 5. The gene structure 6 of a population refers to the distribution of the frequencies of different alleles (911-5) on a given locus (911-4) within the members of the population. The genotypic structure 7 of a population refers to the distribution of different genotypes on the same locus.

915

In the case of an inbred individual, i.e., an individual whose parents have a common ancestor, two genes are said to be identical genes 1 by descent, if both were carried by the same ancestor and are on the same locus. The probability that an individual chosen at random in a population carries two genes identical by descent is the coefficient of inbreeding 2 of the population. The coefficient of kinship 3 of a population is the probability that two individuals chosen at random in that population carry genes identical by descent on the same locus.

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Go to: Introduction to Demopædia | Instructions on use | Downloads
Chapters: Preface | 1. General concepts | 2. The treatment and processing of population statistics | 3. Distribution and classification of the population | 4. Mortality and morbidity | 5. Nuptiality | 6. Fertility | 7. Population growth and replacement | 8. Spatial mobility | 9. Economic and social aspects of demography
Pages: 10 | 11 | 12 | 13 | 14 | 15 | 16 | 20 | 21 | 22 | 23 | 30 | 31 | 32 | 33 | 34 | 35 | 40 | 41 | 42 | 43 | 50 | 51 | 52 | 60 | 61 | 62 | 63 | 70 | 71 | 72 | 73 | 80 | 81 | 90 | 91 | 92 | 93
Index: Global Index | Index of chapter 1 | Index of chapter 2 | Index of chapter 3 | Index of chapter 4 | Index of chapter 5 | Index of chapter 6 | Index of chapter 7 | Index of chapter 8 | Index of chapter 9