A status of guinea fowl (Numida meleagris) and pheasant (Phasianus colchicus) population transferred from wildlife to the breeding assessed based on the histone H1.c’ polymorphic variation

The genetic changes accompanying a relocation of population to the captivity are mostly adverse and usually associated with deterioration of its status. These alterations are greater in small populations in which a loss of genetic variation limits the capability to adaptation. In this work, a status of small-sized guinea fowl and pheasant population relocated to the breeding is presented. These populations were analyzed based on the polymorphism of histone H1.c’, the protein for the first time identified as a heterogeneous. Histone H1.c’ was resolved in the two-dimensional polyacrylamide gel into the isoform H1.c’1 and H1.c’2, so its heterogeneity corresponds to the presence of homozygous phenotypes c’1 and c’2. Because no histone H1.c’ heterozygous phenotype was found, a significant phenotypic diversity in the guinea fowl ( P = 0.023) and pheasant ( P = 0.018) population was detected, together with its departures from Hardy-Weinberg equilibrium ( P < 0.0001). Both populations characterize an extreme loss of genetic diversity due to complete inbreeding ( F = 1) and an impact of genetic drift which, according to the expected values for guinea fowl (0.192) and pheasant (0.182) population, may strongly diminish allele frequency in the following generations. Thus, condition of populations evaluated based on the histone H1.c’ polymorphic variants, recognized as reasonable informative genetic markers (polymorphism information content of guinea fowl = 0.4 and pheasant = 0.38), corresponds to reduction of genetic variability caused by inbreeding and genetic drift. Therefore, it seems that rearing in the captivity can bring negative effects that favor restriction of animals’ vitality and survival of the population.

Topoisomerase IIα Is Required for Embryonic Development and Liver Regeneration in Zebrafish

ABSTRACT Topoisomerases solve the topological problems encountered by DNA throughout the lifetime of a cell. Topoisomerase IIα, which is highly conserved among eukaryotes, untangles replicated chromosomes during mitosis and is absolutely required for cell viability. A homozygous lethal mutant, can4, was identified in a screen to identify genes important for cell proliferation in zebrafish by utilizing an antibody against a mitosis-specific marker, phospho-histone H3. Mutant embryos have a decrease in the number of proliferating cells and display increases in DNA content and apoptosis, as well as mitotic spindle defects. Positional cloning revealed that the genetic defect underlying these phenotypes was the result of a mutation in the zebrafish topoisomerase IIα (top2a) gene. top2a was found to be required for decatenation but not for condensation in embryonic mitoses. In addition to being required for development, top2a was found to be a haploinsufficient regulator of adult liver regrowth in zebrafish. Regeneration analysis of other adult tissues, including fins, revealed no heterozygous phenotype. Our results confirm a conserved role for TOP2A in vertebrates as well as a dose-sensitive requirement for top2a in adults.

Fibrinogen Manchester. Detection of a heterozygous phenotype in the intraplatelet pool

Family members heterozygous for the congenitally abnormal fibrinogen designated fibrinogen Manchester, A alpha 16Arg→His, have previously been shown by h.p.l.c. and amino acid analysis to release a variant fibrinopeptide, [His16]fibrinopeptide A, from plasma fibrinogen after the addition of thrombin. The present study was designed to determine if the same abnormal phenotype was also present in the intraplatelet fibrinogen pool. Fresh platelets were washed in buffers containing EDTA until it could be shown that all washable plasma fibrinogen was removed. Normal platelets were then lysed by freezing and thawing to release their intracellular proteins, which were then treated with thrombin. The fibrinopeptides, cleaved from the intraplatelet fibrinogen, could be detected by an optimized h.p.l.c. technique. Quantification of the intraplatelet fibrinogen gave a result (means +/- S.D., n = 5) of 110 +/- 30 and 90 +/- 30 micrograms/10(9) platelets, when determined by h.p.l.c. quantification of fibrinopeptide B content and fibrinogen fragment E radioimmunoassay respectively. Examination of fibrinopeptides released from the platelet fibrinogen from the family with fibrinogen Manchester with the same techniques showed elution peaks in the same positions as both [His16]fibrinopeptide A and normal fibrinopeptide A. The identity of these peaks was further substantiated by analysis of the h.p.l.c. peaks by using specific radioimmunoassay to fibrinopeptide A. Our results therefore demonstrate that platelet fibrinogen expresses the heterozygous A alpha 16His phenotype. This supports the view that the A alpha chains of platelet and plasma fibrinogen are produced from a single genetic locus.

Clonal origin of cells restricted to monocytic differentiation in acute nonlymphocytic leukemia

Two patients with acute monocytic leukemia and heterozygous for the Mediterranean variant of the X-linked enzyme, glucose-6-phosphate dehydrogenase (G6PD), were investigated to determine the number and type of progenitor cells involved. Mosaicism for Mediterranean G6PD was assessed by the different rate of utilization of 2-deoxy glucose-6- phosphate (2dG6P) by normal and Mediterranean variants of G6PD. The monocytoid blasts were found to express one type of G6PD only, indicating their clonal origin from a common progenitor cell, whereas all other hemopoietic cell populations tested expressed the heterozygous phenotype. The finding of a unique involvement of the monocytic line in two cases of acute nonlymphocytic leukemia (ANLL) represents further evidence of heterogeneity of stem cell involvement in ANLL.

Clonal origin of cells restricted to monocytic differentiation in acute nonlymphocytic leukemia

Two patients with acute monocytic leukemia and heterozygous for the Mediterranean variant of the X-linked enzyme, glucose-6-phosphate dehydrogenase (G6PD), were investigated to determine the number and type of progenitor cells involved. Mosaicism for Mediterranean G6PD was assessed by the different rate of utilization of 2-deoxy glucose-6- phosphate (2dG6P) by normal and Mediterranean variants of G6PD. The monocytoid blasts were found to express one type of G6PD only, indicating their clonal origin from a common progenitor cell, whereas all other hemopoietic cell populations tested expressed the heterozygous phenotype. The finding of a unique involvement of the monocytic line in two cases of acute nonlymphocytic leukemia (ANLL) represents further evidence of heterogeneity of stem cell involvement in ANLL.

Lymphocyte proteins in Huntington's disease: quantitative analysis by use of two-dimensional electrophoresis and computerized densitometry.

We used quantitative two-dimensional electrophoresis to study lymphocyte proteins in Hungtington's disease. Three hundred and six polypeptides from 14C-labeled, phytohemagglutinin-stimulated lymphocytes were measured for variation in relative spot density and 186 for variation in spot position by use of a computer program requiring operator interaction. Each polypeptide was measured in a total of 30 electrophoretograms from 28 individuals, including 13 with Huntington's disease, 2 at risk for it, and 13 controls. The study included two sets of identical twins and, as neurological controls, individuals with neurofibromatosis, Alzheimer's disease, or Shy-Drager syndrome. Seven protein polymorphisms were identified among the 186 most dense polypeptides of each gel, corresponding to a minimum average heterozygosity of 1.4%. Stringent criteria were used to define polymorphic proteins, including observation of at least one individual with each of two homozygous phenotypes and one with the heterozygous phenotype, demonstration of the expected gene dosage relationship by quantitative densitometry, consistency with genetic relationships, and reproducibility. One polymorphic protein showed three electrophoretically variant alleles. Our identification of seven polymorphisms among the 186 proteins measured on a single electrophoretogram illustrates the potential of this technique for performing linkage analysis in diseases of genetic origin. However, we observed no quantitative or positional protein variations that were characteristic of (i.e. specific for) Huntington's disease.