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We study different physical, chemical, or biological processes involving replication, transformation, and disappearance processes, as well as transport processes, and assume that the time and space dependence of the species densities are known. We derive two types of Fisher equations The first type relates the average value of the time derivative of the relative time-specific rates of growth of the different species to the variance of the relative, time-specific rates of growth. A second type relates the average value of the gradient or the divergence of the relative, space-specific rates of growth to the space correlation matrix of the relative, space-specific rates of growth. These Fisher equations are exact results, which are independent of the detailed kinetics of the process: they are valid whether the evolution equations are linear or nonlinear, local or nonlocal in space and/or time and can be applied for the study of a large class of physical, chemical, and biological systems described in terms of time- and/or space- dependent density fields. We examine the implications of our generalized Fisher relations in population genetics, biochemistry, and chemical kinetics (reaction-diffusion systems). We show that there is a connection between the enhanced (hydrodynamic) transport of mutations induced by population growth and space-specific rate vectors: the velocity of enhanced transport is proportional to the product of the diffusion coefficient of the species and the space rate vector; this relation is similar to a fluctuation-dissipation relation in statistical mechanics. [ABSTRACT FROM AUTHOR]

The Human Genome Project, in accomplishing its goal of sequencing one human genome, heralded a new era of research, a component of which is the systematic study of human genetic variation. Despite delays, the Human Genome Diversity Project has started to make progress in understanding the patterns of this variation and its causes, and also promises to provide important information for biomedical studies. [ABSTRACT FROM AUTHOR]

Analysis of 89 biallelic polymorphisms in 523 Turkish Y chromosomes revealed 52 distinct haplotypes with considerable haplogroup substructure, as exemplified by their respective levels of accumulated diversity at ten short tandem repeat (STR) loci. The major components (haplogroups E3b, G, J, I, L, N, K2, and R1; 94.1%) are shared with European and neighboring Near Eastern populations and contrast with only a minor share of haplogroups related to Central Asian (C, Q and O; 3.4%), Indian (H, R2; 1.5%) and African (A, E3*, E3a; 1%) affinity. The expansion times for 20 haplogroup assemblages was estimated from associated STR diversity. This comprehensive characterization of Y-chromosome heritage addresses many multifaceted aspects of Anatolian prehistory, including: (1) the most frequent haplogroup, J, splits into two sub-clades, one of which (J2) shows decreasing variances with increasing latitude, compatible with a northward expansion; (2) haplogroups G1 and L show affinities with south Caucasus populations in their geographic distribution as well as STR motifs; (3) frequency of haplogroup I, which originated in Europe, declines with increasing longitude, indicating gene flow arriving from Europe; (4) conversely, haplogroup G2 radiates towards Europe; (5) haplogroup E3b3 displays a latitudinal correlation with decreasing frequency northward; (6) haplogroup R1b3 emanates from Turkey towards Southeast Europe and Caucasia and; (7) high resolution SNP analysis provides evidence of a detectable yet weak signal (<9%) of recent paternal gene flow from Central Asia. The variety of Turkish haplotypes is witness to Turkey being both an important source and recipient of gene flow. [ABSTRACT FROM AUTHOR]

Examines a paper which focuses on genetics and origin of species. Procedure used for the examination of genetic history of a group of populations; Basis for suggestion that genetic differentiation of the population is mostly due to population fissions; Description of the absolute genetic dating method; Revelations following multivariate analyses.

Discusses various migration processes and their effects on the genetic structure and makeup of populations. Discussion on individual migration; exchange among genetically differentiated populations, and demic diffusion; Analyses of data from the discussions; Implications of the findings to human population expansion and evolution.

The phylogeography of Y-chromosome haplogroups E (Hg E) and J (Hg J) was investigated in >2,400 subjects from 29 populations, mainly from Europe and the Mediterranean area but also from Africa and Asia. The observed 501 Hg E and 445 Hg J samples were subtyped using 36 binary markers and eight microsatellite loci. Spatial patterns reveal that (1) the two sister clades, J-M267 and J-M172, are distributed differentially within the Near East, North Africa, and Europe; (2) J-M267 was spread by two temporally distinct migratory episodes, the most recent one probably associated with the diffusion of Arab people; (3) E-M81 is typical of Berbers, and its presence in Iberia and Sicily is due to recent gene flow from North Africa; (4) J-M172(xMl2) distribution is consistent with a Levantine/ Anatolian dispersal route to southeastern Europe and may reflect the spread of Anatolian farmers; and (5) E-M78 (for which microsatellite data suggest an eastern African origin) and, to a lesser extent, J-M12(M102) lineages would trace the subsequent diffusion of people from the southern Balkans to the west. A 7%-22% contribution of Y chromosomes from Greece to southern Italy was estimated by admixture analysis. [ABSTRACT FROM AUTHOR]