Expression of hepatitis B virus genes in early embryonic cells originated from hamster ova and human spermatozoa transfected with the complete viral genome

Aim： To detect the expression of hepatitis B virus （HBV） genes （HB S and C genes） in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization （IVF） technique. Methods： Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method. Polymerase chain reaction （PCR） was used to detect HB S and pre-Core/Core （pre-C/C） coding genes both in one- and two-cell embryos. Reverse transcription-PCR （RT-PCR） analysis was used to study the expression of the two genes. Fluorescence in situ hybridization （FISH） analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome. Results： Both HB S and pre-C/C coding genes are present and transcribed in one- and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences. Conclusion： Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells. These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line.

Genetic Variation among Fragmented Populations of Atriplex halimus L. Using Start Codon Targeted (SCoT) and ITS1-5.8S-ITS2 Region Markers

Two forms of A. halimus shrubs: erect habit (A. halimus) and bushy habit shrub (A. schweinfurthii) are used naturally isolated by a considerable distance from each other and occupy the same area. To explore the effect of natural isolation on the genetic basis of the two forms, Start Codon Targeted (SCoT) and the phylogenetic relationships of A. halimus by sequencing ITS1-5.8S-ITS2 regions of the ribosomal DNA are used. Significant isolation-by-distance relationship was found (r = 0.62, P = 0.001). Soil factors did not influence molecular variations. The natural isolation of A. halimus habitats restricts gene flow among the populations and the observed high within-population genetic diversity (74.19%) in this species is best explained by its outcrossing behaviour, long-lived individuals and overlapping generations. The UPGMA analysis of the SCoT results showed that all the studied populations were divided into two discrete genetic groups with significant separation of the two forms in Burg El-Arab area (Populations 1 and 2) and insignificant separation between two forms in El-Hammam area (population 5 and 6). The sequencing of the ITS1-5.8S-ITS2 rDNA regions also showed the insignificant separation of the two A. halimus forms. We conclude that gene flow depending on habitat fragmentation was the main factor affecting the population genetic differentiation. We suggest that the two forms do not merit specific rank in presence of interference between the two forms and absence of a breeding barrier fail to separate the different populations when they become sympatric.

Expression of hepatitis B virus genes in early embryonic cells originated from hamster ova and human spermatozoa transfected with the complete viral genome

Aim:To detect the expression of hepatitis B virus(HBV)genes(HB S and C genes)in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization(IVF) technique.Methods:Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method.Polymerase chain reaction(PCR)was used to detect HB S and pre-Core/Core(pre-C/C)coding genes both in one-and two-cell embryos.Reverse transcription-PCR(RT-PCR)analysis was used to study the expression of the two genes.Fluorescence in situ hybridization(FISH)analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome.Results:Both HB S and pre-C/C coding genes are present and transcribed in one-and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences.Conclusion:Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells.These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line.

Use of Random Amplified Polymorphic DNA Analysis for Economically Important Food Crops

The objective of this review is to summarize numerous studies on the use of the random amplified polymorphic DNA （RAPD） technique on rice, corn, wheat, sorghum, barley, rye, and oats to examine its feasibility and validity for assessment of genetic variation, population genetics, mapping, linkage and marker assisted selection, phylogenetic analysis, and the detection of somaclonal variation. Also we discuss the advantages and limitations of RAPD. Molecular markers have entered the scene of genetic improvement in different fields of agricultural research. The simplicity of the RAPD technique made it ideal for genetic mapping, plant and animal breeding programs, and DNA fingerprinting, with particular utility in the field of population genetics.