1022-7954/05/4110- © 2005 Pleiades Publishing, Inc.
Russian Journal of Genetics, Vol. 41, No. 10, 2005, pp. 1168–1175. Translated from Genetika, Vol. 41, No. 10, 2005, pp. 1419–1427.
Original Russian Text Copyright © 2005 by Moskaleichik.
Human economical activity may result in a crucial
reorganization of the genetic structure of natural and
agricultural populations, ultimately leading to a reduc-
tion in their natural reproductive capability.
Understanding the genetic mechanisms underlying
these adverse processes have become possible owing to
a long-term detailed monitoring of the genetic structure
of natural and agricultural populations [1, 2]. The
results of these studies are partly reviewed in a recently
appeared collective monograph . Today the nature of
adverse genetic processes is no longer an enigma and
can be interpreted quantitatively.
The adverse genetic processes are based on a disrup-
tion of the historically formed structure of the total gene
) of a subdivided population. According to
Nei , this diversity includes the intrapopulation com-
ponent and the interpopulation component
are the allele frequency and heterozy-
gosity at the given locus in subpopulation
are their respective mean values averaged over all sub-
is the number of subpopulations
forming the population system.
In intact natural population systems, the proportion
is maintained constant because of a bal-
ance between inbreeding (whose intensity is inversely
proportional to the effective population size
outbreeding (whose intensity is determined by the level
of migration exchange
between subpopulations). The
equilibrium value of the local differentiation depends
, which is species-speciﬁc .
An anthropogenic intervention disturbs the equilib-
rium state of the system. On the one hand, such inter-
vention may disrupt the historically formed demo-
graphic structure of the species, shifting
results in a disturbance of the balance between inbreed-
ing and outbreeding. On the other hand, the anthropo-
genic factor may act as selection favoring extreme phe-
As shown by Altukhov [5–7], populations of bisex-
ual species have a universal polygenic system, deter-
mining the relationship between multilocus allozyme
heterozygosity, developmental rate, and linear body
size (Fig. 1). Multiple homozygotes and multiple het-
erozygotes at allozyme loci accumulate at the opposite
sides of the distribution of adaptive quantitative traits,
while genotypes with intermediate heterozygosity are
closer to the mean values of all of these traits (the adap-
Thus, selection for extreme phenotypes is in fact
selection in favor of multiple homozygotes (heterozy-
gotes), depending on the direction of its biometric vec-
tor. In the former case, the effect of selection is analo-
gous to inbreeding; in the latter, to outbreeding .
Relationship between the Reproductive Capability
of a Subdivided Population and Its Genetic Structure:
Computer Simulation, the Simplest Multilocus Model
F. F. Moskaleichik
Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991 Russia
fax: (095) 132-89-62; e-mail: firstname.lastname@example.org
Received February 8, 2005
—An original computer model, simulating joint genetic and demographic dynamics of subdivided pop-
ulations, is proposed. The model accounts for the reverse effect of the genetic structure on the reproductive capa-
bility of a population, which is based on a postulated limited set of biallelic loci, controlling variation in an adap-
tive quantitative trait. The model allows to simulate spreading of the population, originating from a single small
colony, resulting in establishment of involves genetic and demographic equilibrium (a normal population-genetic
process) and reorganization of the genetic structure of the subdivided population under anthropogenic pressure,
associated with a decrease in its reproductive capability (an adverse population-genetic process).