Vol 51, No 4 (2017)

The effect of γ-irradiation treatment of seeds of intra- and interspecific F₁ hybrid tomatoes on distortion of Mendelian monohybrid segregation, crossover variability, and recombination frequency of unlinked marker genes of chromosomes 2 and 6 was studied. It was found that more significant distortion effect on the segregation of marker loci of studied chromosomes was detected for seed treatment with 130 Gy. The significant direct relationship between Mendelian segregation for m-2 gene and a rf_m-2c vaue for 60 Gy and for aw and m-2 genes and rf_awc, _awm-2 values for 60 and 130 Gy treatment in combination Mo500 × var. cerasiforme was revealed. The latter corresponds to the effect of “quasirepulsion.”

Mutation analysis of gene GLB1 in 26 patients from different regions of Ukraine diagnosed with GM1-gangliosidosis identified 15 pathogenic mutations. The most common was missense mutation p.His281Tyr (c.841C>T) in exon 8, which was found in at least one allele in 16 of 26 patients (61.5%), accounting for 20 of 52 (38.5%) mutant alleles. Mutation p.His281Tyr (c.841C>T) was described in rare cases in patients from Germany, Italy, and Portugal, while no alleles with such a replacement were found in other countries. This may indicate a much higher frequency of this mutation in Ukraine compared to other countries. Analysis of the information about the spatial distribution of the families with mutation p.His281Tyr (c.841C>T) revealed that most of the alleles with this mutation (14 of 20 or 70%) were found in patients from the western regions of the country, which may be due to the founder effect.

Increase in the degree of consanguinity of Holstein breed identified to the best-cultivated dairy breeds is one of the major ways to improve the genotypes of the dairy cattle in many countries all over the world. The widespread biotechnology and large-scale selection adoption reduced the range of the used bull sires in dairy stockbreeding, which resulted in the occurrence of different abnormalities associated with the inheritance caused by gene mutations and chromosomal disorders in the newborn calves. Since the main part of such abnormalities has a recessive inheritance pattern, they represent a hidden genetic load, which is not always expressed in a phenotype. In recent years, the cytogenetic and karyotyping approaches have become more widespread and are required for both the detailed theoretical prerequisites and the applied problem solutions to prevent losses in agricultural production. The results of the cytogenetic analysis of the North- Caucasian population of Holstein cows having problems in reproduction have been reported. The aberrant cells are detected (frequency of occurrence is 5.35%); the number of aberrations per analyzed cell (0.05/1.0) is determined; the absence of the reciprocal translocations in a karyotype in the analyzed livestock is revealed. The genealogical interrelations of ancestors of the lines of Montivik-Chifteyn no. 95679 and Reflekshn- Sovering no. 198998 bull sires with the values for stillbirth incidence among their progeny have been traced.

The ability of living organisms to perceive electromagnetic radiation is one of the most intriguing issues that concern the fundamental problem of interaction of living matter with the factors of physical nature. Polyphosphates can be possible receptors. The purpose of the study was to evaluate the role of the polyphosphatases PPN1 and PPX1 in the cell response to exposure to electromagnetic fields (EMFs) of 1871 MHz that were generated by DCS-1800 base stations. Six-week exposure at energy flux densities of 0.1–10 W/m² was used. The corresponding values of specific adsorption rate (SAR) were 0.0075–1.5 W/kg. Electromagnetic radiation was found to lead to the impairment of a number of physiological and metabolic functions of cells, change their resistance to antibiotics, and result in irreversible changes in their genome. Low doses of the EMF caused the strongest biological responses. It was demonstrated that the deficiency in the ppn1 and ppx1 genes made the strains less adaptive, which resulted in an increase in their sensitivity to EMF exposure. Both polyphosphatases PPN1 and PPX1 were shown to be necessary for the normal cell response to the nonionizing electromagnetic radiation of 1871 MHz.

Phytophthora capsici is the most destructive pathogen of vegetables that has blown a serious threat to chili pepper plants. We discussed the control of Phytophthora capsici through manipulation of genetic architecture of chili plant. Various genes encoding transcriptional regulatory and defense related putative proteins such as pathogen-related protein (PR), Anti-Microbial peptides (AMPs), Polygalacturonase-inhibiting proteins (PGIPs), Lipid Transfer Protein (LTP), Pectin Methylesterase (PME), Leucine-rich repeat proteins (LRRs), Osmotin-like and Thaumatin-like protein, have been identified in Capsicum. We also discussed the enhanced resistance to P. capsici infection by treatment with a variety of abiotic and biotic inducers that act on defense signaling pathways involved in disease resistance. We highlighted the vulnerability of chili crop with reference to its genetic resources against Phytophthora blight. Disease control through chemicals is becoming problematic, so we proposed other ways to control the disease severity.

The first cytogenetic comparisons of five snapper species from Thailand were presented here. Renal cell samples were taken from blacktail snapper (Lutjanus fulvus), five lined snapper (L. quinquelineatus), dory snapper (L. fulviflamma), brownstripe red snapper (L. vitta), and mangrove red snapper (L. argentimaculatus). The mitotic chromosome preparation was prepared directly from kidney cells. Conventional staining and Ag-NOR banding techniques were applied to stain the chromosomes. The results exhibited that all five snapper species have the diploid chromosome numbers of 2n = 48 and the fundamental numbers (NF) of 48. The presences of large, medium, and small telocentric chromosomes were 22-24-2, 24-20-4, 36-10-2, 28-16-4 and 36-10-2, respectively. The Ag- NORs banding technique provides the pair of nucleolar organizer regions (NORs) at subcentromeric region of the long arm of the respective telocentric chromosome pairs 9, 1, 3, 4 and 9. Their karyotype formulas is as follows: L. fulvus (2n = 48): L₂₂^t + M₂₄^t + S₂^t, L. quinquelineatus (2n = 48): L₂₄^t + M₂₀^t + S₄^t, L. fulviflamma (2n = 48): Lt36 + Mt10 + St2, L. vitta (2n = 48): L₂₈^t + M₁₆^t + S₄^t, and L. argentimaculatus (2n = 48): L₃₆^t + M₁₀^t + S₂^t.