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We have developed a simple and efficient method to construct partial libraries of swine Chromosome (Chr) 11, starting with only 300 flow-sorted copies. DNA is amplified by PARM-PCR with primer containing at the 5'-end the sequence AGCU-. After amplification, digestion of PCR products with uracil DNA glycosylase generates cohesive ends corresponding to the SstI site. The amplified fragments can then be ligated in vector linearized with the SstI enzyme. Using five different primers, we PARM-PCR amplified and cloned swine Chr 11 DNA. These chromosome-specific libraries have been used to develop 14 different (TG)n microsatellites. Ten of these markers were assigned to Chr 11 by PCR analysis of a panel of Pig-Rodent somatic hybrids and by linkage analysis of the 171 individuals of the PiGMaP reference families. A complete linkage map of 147 cM of this chromosome was then realized by integrating existing markers.

The authors show that the operating wavelength range of a 10 Gbit/s single-channel soliton system using sliding-frequency guiding filters over a 18 Mm distance reduces from 1.3 to 0.2 nm when the system is upgraded to 20 Gbit/s with a second wavelength channel. A record WDM propagation distance > 19 Mm is obtained by tuning the channels in the centre of the operating wavelength range. This result is achieved without the use of dispersion management.

The murine Ity/Lsh/Bcglocus belongs to a conserved region between mouse Chromosome 1 and human chromosome 2. This gene governs mouse resistance to several intracellular pathogens. We have localized the gene on sheep chromosome 2q41→q42 by radioactive in situ hybridization using a 2.1-kb fragment of the ovine equivalent of this gene.

Epigenetic phenomena, such as DNA methylation, which participate in the regulation of gene expression, can influence phenotypes. The influence of the embryonic environment on the adult phenotype, through epigenetic marks, has been observed in numerous cases. Recent studies show that epigenetic information may be transmitted across generations. Our aim was to observe if a modification of the quail embryonic environment would have transgenerational effects. We observed phenotypic differences in the third generation between 2 lines, obtained after treating (Epi+) or not treating (Epi-) eggs from a common set of founders G0, by injection of genistein. We used genistein as it is known to interfere with the epigenome, especially with DNA methylation. A “mirror” device was set, with parallel genealogies in each line, to minimize the putative influence of genetics on trait variability. After 3 generations without any further treatment, a significant difference in sexual maturity was observed between the lines, with the Epi+ G3 birds starting egg laying later. A significant interaction between line and sex was observed for 3-wk body weight and for eye temperature. Two behavioral traits in the G3 were also significantly affected by the initial treatment. Global methylation analyses are ongoing. These observations demonstrate the impact of a modification of the founders’ embryonic environment on the phenotype of quails, 3 generations later. While genetic variability cannot definitely be ruled out, the mirror animal device should have minimized its effects, and observed differences in the G3 may be attributed, at least partly, to transgenerational epigenetic phenomena.

Interplay between chromatic dispersion and amplifier spacing is analysed in 20 Gbit/s syncnronously modulated soliton systems over 20 Mm distance. It is shown that the range of dispersion enabling error free transmission decreases as the amplifier spacing increases and can be improved by enhanced intensity/phase modulation depth.

70 µm2 large effective area fibres are exploited in a 5 Gbit/s soliton transmission system over transoceanic distances. It is shown that the use of large effective area fibres improves the system performance by enhancing either the total transmission distance or the amplifier spacing.