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Discusses the genetic maps of human and animal genomes. Emergence and disappearance of mammalian species; Evolution of genetic science; Development of mammalian gene maps; Efforts to understand genetic distribution to diseases and other biological phenomena; Biomedical applications of comparative genomics; Significance of comparative genomics.

Two human genes that are homologous to both the murine transforming gene (oncogene) v-raf and the chicken transforming gene v-mil have been mapped by means of human-rodent somatic cell hybrids to human chromosomes previously devoid of known oncogenes. One gene, c-raf-2, which appears to be a processed pseudogene, is located on chromosome 4. The other gene, c-raf-1, which appears to be the active gene, is located on chromosome 3 and has been regionally mapped by chromosomal in situ hybridization to 3p25. This assignment correlates with specific chromosomal abnormalities associated with certain human malignancies. [ABSTRACT FROM AUTHOR]

Studies means of choosing mammalian genomes for sequencing. Overview on advances in genomics research through the years; Morphological and physiological differences in mammalian genetic structure; Phylogenetic relationships among modern orders of placental mammals.

Examines reasons behind selecting dog for full-genome sequencing by researchers. Goals of the International Human Genome Project; Progress registered in dog genetics; Process used in building dog genome sequence.

Investigates the resolution of the early placental mammal radiation using Bayesian phylogenetics. Basal split between Afrotheria and other placentals; Separation between South America and Africa in the Cretaceous; Ancestry of the crown-group Eutheria in the Southern Hemisphere.

Focuses on the Mmu 16 draft sequence. Use of a whole-genome shotgun sequence assembly; Comparison between the chromosome segments of mouse and human; Importance of close conservation of sequence; Factors contributing to the constraining rapid divergence of default neutral sequences.

The rediscovery of remnant Florida panthers (Puma concolor coryi) in southern Florida swamplands prompted a program to protect and stabilize the population. In 1995, conservation managers translocated eight female pumas (P. c. stanleyana) from Texas to increase depleted genetic diversity, improve population numbers, and reverse indications of inbreeding depression. We have assessed the demographic, population-genetic, and biomedical consequences of this restoration experiment and show that panther numbers increased threefold, genetic heterozygosity doubled, survival and fitness measures improved, and inbreeding correlates declined significantly. Although these results are encouraging, continued habitat loss, persistent inbreeding, infectious agents, and possible habitat saturation pose new dilemmas. This intensive management program illustrates the challenges of maintaining populations of large predators worldwide. [ABSTRACT FROM AUTHOR]

The world's domestic cats carry patterns of sequence variation in their genome that reflect a history of domestication and breed development. A genetic assessment of 979 domestic cats and their wild progenitors—Fells silvestris silvestris (European wildcat), F. s. lybica (Near Eastern wildcat), F. s. ornata (central Asian wildcat), F. s. cafra (southern African wildcat), and F. s. bieti (Chinese desert cat)—indicated that each wild group represents a distinctive subspecies of Fells silvestris. Further analysis revealed that cats were domesticated in the Near East, probably coincident with agricultural village development in the Fertile Crescent. Domestic cats derive from at least five founders from across this region, whose descendants were transported across the world by human assistance. [ABSTRACT FROM AUTHOR]

Modem felid species descend from relatively recent (<11 million years ago) divergence and speciation events that produced successful predatory carnivores worldwide but that have confounded taxonomic classifications. A highly resolved molecular phytogeny with divergence dates for all living cat species, derived from autosomal, X-linked, Y-linked, and mitochondrial gene segments (22,789 base pairs) and 16 fossil calibrations define eight principal lineages produced through at least 10 intercontinental migrations facilitated by sea-level fluctuations. A ghost lineage analysis indicates that available felid fossils underestimate (i.e., unrepresented basal branch length) first occurrence by an average of 76%, revealing a low representation of felid lineages in paleontological remains. The phylogenetic performance of distinct gene classes showed that Y-chromosome segments are appreciably more informative than mitochondrial DNA, X-linked, or autosomal genes in resolving the rapid Felidae species radiation. [ABSTRACT FROM AUTHOR]

Investigates the DNA sequence variation in four nuclear genes of African forest and savannah elephants. Phylogenetic distinctions between the two elephant species; Nucleotide site differences; Morphological and habitat distinctions; Hybridization of gene flow between the elephant species.

Examines the effects of increased heterozygosity on the development of AIDS in patients infected with HIV-1. Delay of the onset of AIDS in those with maximum human leukocyte antigen (HLA) heterozygosity of class I loci; Homozygosity of loci and the development of AIDS; HLA class I alleles B*35 and Cw*04 associated with the development of AIDS in Caucasians; Heterozygosity and survival rate.

Presents research which studied the progression of HIV-1 in patients with various kinds of CCR5 promoter genotypes. CCR5 gene encoding in macrophage-tropic (R5) strains of HIV-1; Results of genetic association analysis; Results of composite genetic epidemiologic analyses; Reasons for variations in progression; Multigenic nature of host factors limiting AIDS disease progression.

Several of the endothelial cell polypeptide mitogens that have been described probably play a role in blood vessel homeostasis. Two overlapping complementary DNA clones encoding human endothelial cell growth factor (ECGF) were isolated from a human brain stem complementary DNA library. Southern blot analysis suggested that there is a single copy of the ECGF gene and that it maps to human chromosome 5 at bands 5q31.3 to 33.2. A 4.8-kilobase messenger RNA was present in human brain stem messenger RNA. The complete amino acid sequence of human ECGF was deduced from the nucleic acid sequence ofthese dones; it encompasses all the well-characterized acidic endothelial cell polypeptide mitogens described by several laboratories. The ECGF-encoding open reading frame is flanked by tranislation stop codons and provides no signal peptide or internal hydrophobic domain for the secretion ofECGF. This property is shared by human interleukin-1, which is approximately 30 percent homologous to ECGF. [ABSTRACT FROM AUTHOR]

Natural killer (NK) cells provide a central defense against viral infection by using inhibitory and activation receptors for major histocompatibility complex class I molecules as a means of controlling their activity. We show that genes encoding the inhibitory NK cell receptor KIR2DL3 and its human leukocyte antigen C group"! (HLA-C1) ligand directly influence resolution of hepatitis C virus (HCV) infection. This effect was observed in Caucasians and African Americans with expected low infectious doses of HCV but not in those with high-dose exposure, in whom the innate immune response is likely overwhelmed. The data strongly suggest that inhibitory NK cell interactions are important in determining antiviral immunity and that diminished inhibitory responses confer protection against HCV. [ABSTRACT FROM AUTHOR]