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Gene-based technologies offer the world unprecedented opportunities for improving quality of life, or for reducing it in irreversible ways. The basic question addressed in this paper is the position and response of international bodies and donors on whether or not to provide gene-based technologies to developing countries. It will not be easy to attain a responsible and coherent answer to this challenging question. Gaining an objective understanding of the essential issues is hard when controversy rages across the supposedly neutral scientific facts. Nevertheless, the outcome of the discussion is of prime importance at a global level. This paper seeks to bring light into this arena. After the Introduction, three principle concerns are examined which should be at the top of the agenda of these international institutions. Following this, short reviews of the critical issues are presented covering: the scientific characteristics and uncertainties associated with gene-based technologies; the nature of target areas in which they may be applied; and the considerable disquiet in society generally. These short outlines highlight the possible benefits and dangers associated with the critical issues. It is concluded that the objectives, capabilities, opportunities and dangers cannot be evaluated at the scientific level alone; they must be evaluated as matters of high policy by all stakeholders before gene-based technologies are implemented on the ground. In view of these perspectives, at the end of the paper it is proposed that scientists should place a moratorium on the development of gene-based technologies for the development of transgenic animals. It is also proposed that, during the moratorium, the United Nations should carry out a global referendum on the desirability of gene-based technologies being applied to the food chain. Meanwhile it is recommended that international organizations and funding bodies should not promote these techniques.

Knowledge of genetic diversity is important as it forms the basis for designing breeding programmes and making rational decisions on sustainable utilization of animal genetic resources. This study was designed to assess the efficiency of blood protein polymorphism as a rapid tool for assessing genetic diversity, using seven blood proteins (transferrin, albumin, haemoglobin, esterase A, esterase C, carbonic anhydrase and X-protein) and 457 indigenous fat-tailed (351) and fat-rumped (106) hair sheep in Kenya from 7 populations, with 40 Merino as controls. Transferrin was analysed using polyacrylamide gel electrophoresis and starch gel electrophoresis was used to analyse the other six loci. Of the seven loci analysed, two — carbonic anhydrase and X-protein — could not be interpreted. The five interpretable markers, however, showed low levels of polymorphism in allele numbers and heterozygosity. Multilocus mean F_ST values of 0.083 indicated a moderate genetic differentiation between the populations analysed. The Dm and Da genetic distance estimates showed the indigenous sheep populations in Kenya to be closely related genetically, with the dendrogram failing to resolve indigenous sheep into fat-tailed sheep and fat-rumped hair sheep. Due to its costs and modest equipment demands, blood protein polymorphism can be used as a rapid tool to assess genetic diversity and prioritize breeds to be analysed by microsatellite DNA markers.

The Red Jungle Fowl ( Gallus gallus ) is generally considered to be main ancestor of the domestic fowl ( Gallus domesticus ). However, it is also believed that other wild Gallus species might have contributed to the modern genetic make-up of the domestic fowl, one wild species being the Ceylon Jungle Fowl ( Gallus lafayetti ), endemic to Sri Lanka, which could have contributed to the domestic stock of Sri Lankan native poultry. The present study was conducted in order to investigate the origin of native fowl in Sri Lanka and to establish genetic relationships among them and the Ceylon Jungle Fowl. Morphological characters of endemic, indigenous and exotic fowl types were recorded. These included Ceylon Jungle fowl; eleven types of native chicken from Sri Lanka; and two exotic chicken breeds (Cornish and Rhode Island Red). Blood samples were collected for DNA extraction. Randomly Amplified Polymorphic DNA (RAPD) analysis was carried out using sixteen non-specific primers. The results of morphological characterization revealed many variations in plumage and colour pattern. Single and pea comb types were found in both native and exotic types of chicken. A prominent yellow colour marking on a red comb was a unique feature in Ceylon Jungle fowl. The presence of white spots in red earlobes was a distinguishing feature of all native chicken types. Sixteen non-specific primers were used in the study, and produced 22 polymorphic bands ranging from 500 to 1960 bp. Genetic similarity indices ranged from 0.5 to 1.1 in average genetic distance scale, indicating a broad genetic base in the samples studied. Cluster analysis revealed a clear separation of Ceylon Jungle Fowl from all other types studied, indicating that there was early separation and divergent evolution of Ceylon Jungle Fowl from all the domestic races studied.

Human clotting factor VIII (hFVIII) is a very complex and large protein whose expression is difficult, as hFVIII requires extensive post-translational modification to be biologically active. This paper reports the generation of transgenic rabbits as a model species for testing the expression of hFVIII in the mammary gland. For micro-injection, a fusion gene construct was used, consisting of 2.5 kb murine whey acidic protein (mWAP) promoter, 7.2 kb cDNA of hFVIII, and 4.6 kb of 3′ flanking sequences of the mWAP gene. from 130 micro-injected zygotes transferred into recipients, 30 offspring were delivered. The pups were screened for the transgene by PCR, using DNA isolated from the ear, and results were confirmed by Southern blot analysis. The transgene was identified in one female founder animal, and it was transmitted to the offspring in a Mendelian fashion, thus demonstrating stable integration of the gene construct into the germline of the transgenic rabbits.

Parentage verification in Indian goat breeds addresses dubious parentage of three types: 1, exclusion of a putative parent when the genotype of one parent and offspring are known; 2, exclusion of a putative parent when the genotype of the other parent is not available; and 3, exclusion of both the parents of an offspring if falsely recorded. The investigation used 116 unrelated goats and six pedigreed families of three breeds of goat (Jamnapari, Barbari and Sirohi). A set of 12 bovine microsatellite markers was analysed for parentage determination in goats for different types of misidentifications. For Type 1 dubious parentage, the exclusion probability for each marker varied widely, from as low as 13.4% (locus BM-5004 in Jamnapari) to as high as 67% (locus BMS-1237 in Sirohi). For type 2, the values of probability of exclusion ranged from 5% (locus BMS-1237 in Barbari) to 50.1% (locus BMS-1237 in Sirohi). For Type 3, exclusion values ranged from 21.6% to 84%. The exclusion probabilities of falsely recorded parents were estimated for different combinations of 5 markers sets with 12, 8, 6, 5 and 4 markers, respectively.

New techniques of molecular biology used in analysing DNA polymorphism give access to the whole genetic variability of a given individual, while traditional blood typing (red cell typing and biochemical polymorphisms) gives access only to the transcribed fraction, which is then translated to protein. In addition, this fraction represents only a tiny part (5 to 10%) of the genome’s coding fraction. One of the newer testing methods in identifying horses is a DNA-based test using microsatellite marker analysis. The objective of this work was to evaluate the efficacy of this new technology in the identification and parentage verification of Arabian, Thoroughbred and Anglo-Arab horses in Morocco. The Anglo-Arab horse is a crossbreed between Arabian and Thoroughbred. Three samples from the three breeds were analysed for 12 microsatellites (HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, AHT4, AHT5, VHL20, HTG10 and ASB2). Blood samples were gathered from a total of 1541 horses: 804 Arabians, 559 Thoroughbreds and 178 Anglo-Arabs. Allelic frequencies of the 12 loci studied were calculated in the three groups. The results allowed the determination of intra-population genetic parameters: heterozygosity ratio (h), probability of identification (P_i) and probability of exclusion (P_e). Based on mean heterozygosity values, variability was relatively lower in Thoroughbred horse (0.7036), while it was almost the same in Arabian and Anglo-Arab horses (respectively 0.7217 and 0.7232). Probabilities of exclusion obtained with the 12 systems were greater than 99.9% for the three populations studied, and probabilities of identification of individual horses were 15.4 × 10^−12, 3.5 × 10^−12 and 3.2 × 10_−12 in the Thoroughbred, Arabian and Anglo-Arab breeds, respectively. These results indicate that the test using microsatellite marker analysis constitutes a highly efficient and reliable alternative for the identification and parentage verification of individual horses and so it is a useful tool for horse breeding and horse registries.

Donor cell lines were developed from skin tissue for the conservation of the endangered Jaiselmeri camel breed of India. Average cell proliferation rates varied from 0.82 to 0.69 in different passages, and population doubling time from 29.3 h to 34.8 h. Around 15 population doublings were accomplished during this culturing. Cell viability was 97 to 99% in different passages. Growth curves of cells from the JC-5 cell line reached a plateau on day 7, while the slower-growing cultures of JC-3 showed elevation even on day 10, possibly due to donor age differences. Cell proliferation rates by both cell count and MTT absorbance showed similar patterns, with a correlation coefficient of 0.79._MTT assay, a colorimetric method, can handle large samples in somatic cell cultures. Diploid chromosomal counts in passages 1, 3 and 5 were normal (2N=74, XY) in 97% of the cells. Occasional metaphase plates showed polyploidy. The present baseline data on standard growth curve, linear relationship in colorimetric assay for estimation of cell proliferation rate, and normal ploidy and karyological levels in camel skin fibroblast cells in multiplication could be useful in developing competent donor somatic cell lines for conservation now and revival of this camel breed by cloning in the future.

Two breeds — Ouled-Djellal and Hamra (85 animals) — were genotyped for 12 microsatellites using PCR and sequencing. Allele number and frequency were calculated, and 141 different alleles were found for these microsatellites, reflecting high genetic variability within these breeds. This study is being extended to other Algerian breeds to estimate variability and genetic distances between them. In parallel, blood samples from the various breeds are being collected to build up a DNA bank. The results should support establishment of a strategy to promote the use and development of locally adapted sheep resources.

Skin samples from ear pinna of 10 male and 10 female sheep were collected and cultured in DMEM+Ham’s F12 nutrient medium. Cell viability was 95 to 100% in different cultures. Mean cell proliferation rates were 0.94-0.67 and 1.15-0.56 for males and females in different passages, respectively. Cell proliferation rates were highest in first passage and then showed an age-related decline. Average cell doubling time was 30 h in males and 29.6 h in females. Skin fibroblast cell growth curves were in lag phase for the first 2 days, entered log phase (3rd to 7th days) and plateaued on day 8. Diploid chromosomal counts in proliferating cells up to the 5th passage were normal (2N=54), with no gross chromosomal aberrations recorded. Cells frozen from cycling cells at 80-90% confluency showed superior post-thaw growth compared with cells from overconfluent cultures. DMSO at 10% (v/v) in freezing media was optimal. Controlled-rate freezing at-1°C/min showed better post-thaw cell viability and growth potential. Direct plating of thawed cells without removing DMSO and other contents of the freezing medium gave better post-thaw survival and proliferation rates.

Aiming at the development of a differential vaccine (DIVA) against infectious bovine rhinotracheitis (IBR), a Brazilian strain of bovine herpesvirus type 1 (BHV1) with a deletion of the glycoprotein E (gE) gene was constructed (265gE^−). Here we present the experiments performed with this strain in order to evaluate its safety and efficacy as a vaccine virus in cattle. In the first experiment, a group of calves was inoculated with 265gE^− and challenged with wild type virus 21 days post-inoculation. Calves immunized with 265gE^− virus and challenged with wild type virus developed very mild clinical disease with a significant reduction in the amount of virus excretion and duration. The safety of the 265gE^− during pregnancy was assessed using 22 pregnant cows, at different stages of gestation, that were inoculated with the 265gE^− virus intramuscularly, with 15 pregnant cows kept as non-vaccinated controls. No abortions, stillbirths or foetal abnormalities were seen after vaccination. The results show that the 265gE^− recombinant is attenuated and able to prevent clinical disease upon challenge. This recombinant will be further evaluated as a candidate virus for a BHV1 differential vaccine.