Helen Mary Sang | |
---|---|
Born | 1955 |
Alma mater | University of Cambridge (BSc, PhD) |
Scientific career | |
Institutions | Roslin Institute University of Edinburgh Harvard University |
Thesis | Studies in genetic recombination in Sordaria brevicollis' (1975) |
Doctoral advisor | Harold Leslie Keer Whitehouse |
Helen Mary Sang OBE FRSE FRSB (born 1955) is the head of the Division of Developmental Biology at the Roslin Institute of the University of Edinburgh. Her research considers the development of chickens that cannot spread avian influenza (bird flu). She has previously served on the Biotechnology and Biological Sciences Research Council.
Sang studied natural sciences at the University of Cambridge and graduated in 1972. [1] She earned her doctorate in the Department of Botany where she studied genetic recombination in Sordaria . She worked in the laboratory of Harold Leslie Keer Whitehouse. After earning her PhD, Sang was awarded a SERC–NATO fellowship to look at mismatch repair in E. coli working with Matthew Meselson at Harvard University. [1]
Sang returned to the United Kingdom as a Medical Research Council fellow working with David Finnegan at the University of Edinburgh. Here she investigated the transposable element that is responsible for the I-R system of hybrid dysgenesis in Drosophila melanogaster . Sang was made principal investigator at the Agriculture and Food Research Council (AFRC) Poultry Research Centre, which became the Roslin Institute in 1993. [1] Sang has dedicated much of her research career to the genetic modification of chickens. [2] In the 1980s when Sang started at the Roslin Institute she started to investigate ways to genetically modify hens so that they created valuable proteins in their eggs. [3] [4] She proposed purifying the egg whites and making use of the engineered proteins for medical therapies to treat cancer, arthritis and multiple sclerosis. [5] Since then, genome editing has evolved so that genes can be inserted into the DNA of chickens, producing new human proteins alongside those in egg white. [6] [7] Working with Lissa Herron Sang demonstrated new ways to purify these egg proteins. [8] In 2019 she demonstrated that these hens could produce IFNalpha2a, a protein which has anti-viral and anti-cancer potential. [9] [10]
She has developed new ways to produce transgenic chickens using lentiviral vectors. [11] [12] The transgenic chickens can serve as models for investigations into vertebrate development. [13] [14] Sang and colleagues developed transgenic lines that incorporated green fluorescent protein and membrane localised green fluorescent proteins in cells that are developing embryos. These could be used for in vivo imaging or grafting to analyse lineage during embryogenesis.
In 2011 together with Laurence Tiley Sang demonstrated that she could genetically modify chickens to confer resistance to avian influenza. [15] [16] [17]
Sang is a fellow of the Royal Society of Edinburgh (2008) and the Royal Society of Biology. [18] From 2015 to 2018 Sang served on the Biotechnology and Biological Sciences Research Council. Sang was appointed Officer of the Order of the British Empire (OBE) in the 2020 New Year Honours for services to food security and bioscience for health. [19] [20]
Her publications include:
Sang has appeared on The Naked Scientists and delivered a TED talk on the need for genetically modified chickens. [21]
Genetically modified maize (corn) is a genetically modified crop. Specific maize strains have been genetically engineered to express agriculturally-desirable traits, including resistance to pests and to herbicides. Maize strains with both traits are now in use in multiple countries. GM maize has also caused controversy with respect to possible health effects, impact on other insects and impact on other plants via gene flow. One strain, called Starlink, was approved only for animal feed in the US but was found in food, leading to a series of recalls starting in 2000.
A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques. The exact definition of a genetically modified organism and what constitutes genetic engineering varies, with the most common being an organism altered in a way that "does not occur naturally by mating and/or natural recombination". A wide variety of organisms have been genetically modified (GM), from animals to plants and microorganisms. Genes have been transferred within the same species, across species, and even across kingdoms. New genes can be introduced, or endogenous genes can be enhanced, altered, or knocked out.
Genetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by artificially synthesising the DNA. A construct is usually created and used to insert this DNA into the host organism. The first recombinant DNA molecule was made by Paul Berg in 1972 by combining DNA from the monkey virus SV40 with the lambda virus. As well as inserting genes, the process can be used to remove, or "knock out", genes. The new DNA can be inserted randomly, or targeted to a specific part of the genome.
The chicken is a domesticated species that arose from the red junglefowl, originally from India. They have also partially hybridized with other wild species of junglefowl. Rooster and cock are terms for adult male birds, and a younger male may be called a cockerel. A male that has been castrated is a capon. An adult female bird is called a hen, and a sexually immature female is called a pullet. Humans keep chickens primarily as a source of food or as pets. Traditionally, they were also bred for cockfighting, which is still practiced in some places. Chickens domesticated for meat are broilers, and for eggs, they are layers.
Genetically modified foods, also known as genetically engineered foods, or bioengineered foods are foods produced from organisms that have had changes introduced into their DNA using various methods of genetic engineering. Genetic engineering techniques allow for the introduction of new traits as well as greater control over traits when compared to previous methods, such as selective breeding and mutation breeding.
Anthony John Clark OBE FRSE was an English molecular biologist who was a founder of applying molecular technology to farm animals. He was director of the Roslin Institute from 2002 to 2004.
A transgene is a gene that has been transferred naturally, or by any of a number of genetic engineering techniques, from one organism to another. The introduction of a transgene, in a process known as transgenesis, has the potential to change the phenotype of an organism. Transgene describes a segment of DNA containing a gene sequence that has been isolated from one organism and is introduced into a different organism. This non-native segment of DNA may either retain the ability to produce RNA or protein in the transgenic organism or alter the normal function of the transgenic organism's genetic code. In general, the DNA is incorporated into the organism's germ line. For example, in higher vertebrates this can be accomplished by injecting the foreign DNA into the nucleus of a fertilized ovum. This technique is routinely used to introduce human disease genes or other genes of interest into strains of laboratory mice to study the function or pathology involved with that particular gene.
Viral vectors are tools commonly used by molecular biologists to deliver genetic material into cells. This process can be performed inside a living organism or in cell culture. Viruses have evolved specialized molecular mechanisms to efficiently transport their genomes inside the cells they infect. Delivery of genes or other genetic material by a vector is termed transduction and the infected cells are described as transduced. Molecular biologists first harnessed this machinery in the 1970s. Paul Berg used a modified SV40 virus containing DNA from the bacteriophage λ to infect monkey kidney cells maintained in culture.
Genetically modified plants have been engineered for scientific research, to create new colours in plants, deliver vaccines, and to create enhanced crops. Plant genomes can be engineered by physical methods or by use of Agrobacterium for the delivery of sequences hosted in T-DNA binary vectors. Many plant cells are pluripotent, meaning that a single cell from a mature plant can be harvested and then under the right conditions form a new plant. This ability is most often taken advantage by genetic engineers through selecting cells that can successfully be transformed into an adult plant which can then be grown into multiple new plants containing transgene in every cell through a process known as tissue culture.
Genetically modified animals are animals that have been genetically modified for a variety of purposes including producing drugs, enhancing yields, increasing resistance to disease, etc. The vast majority of genetically modified animals are at the research stage while the number close to entering the market remains small.
Genetically modified fish are organisms from the taxonomic clade which includes the classes Agnatha, Chondrichthyes and Osteichthyes whose genetic material (DNA) has been altered using genetic engineering techniques. In most cases, the aim is to introduce a new trait to the fish which does not occur naturally in the species, i.e. transgenesis.
Genetically modified rice are rice strains that have been genetically modified. Rice plants have been modified to increase micronutrients such as vitamin A, accelerate photosynthesis, tolerate herbicides, resist pests, increase grain size, generate nutrients, flavors or produce human proteins.
Genetically modified mammals are mammals that have been genetically engineered. They are an important category of genetically modified organisms. The majority of research involving genetically modified mammals involves mice with attempts to produce knockout animals in other mammalian species limited by the inability to derive and stably culture embryonic stem cells.
Genetically modified sperm (GM sperm) is sperm that has undergone genetic modification for biomedical purposes, including the elimination of genetic diseases or infertility. Although the procedure has been tested on animals such as fish, pigs, and rabbits, it remains relatively untested on humans. In the case of pigs, the goal of research is to inexpensively produce organs and supplement the shortage of donated human organs. Although GM sperm has the potential to detect and treat genetic diseases, it will likely take many years for successful use in patients.
AquAdvantage salmon is a genetically engineered (GE) fish, a GE Atlantic salmon developed by AquaBounty Technologies in 1989. The typical growth hormone-regulating gene in the Atlantic salmon was replaced with the growth hormone-regulating gene from Pacific Chinook salmon, with a promoter sequence from ocean pout. This gene enables GM salmon to grow year-round instead of only during spring and summer.
The regulation of genetic engineering varies widely by country. Countries such as the United States, Canada, Lebanon and Egypt use substantial equivalence as the starting point when assessing safety, while many countries such as those in the European Union, Brazil and China authorize GMO cultivation on a case-by-case basis. Many countries allow the import of GM food with authorization, but either do not allow its cultivation or have provisions for cultivation, but no GM products are yet produced. Most countries that do not allow for GMO cultivation do permit research. Most (85%) of the world's GMO crops are grown in the Americas. One of the key issues concerning regulators is whether GM products should be labeled. Labeling of GMO products in the marketplace is required in 64 countries. Labeling can be mandatory up to a threshold GM content level or voluntary. A study investigating voluntary labeling in South Africa found that 31% of products labeled as GMO-free had a GM content above 1.0%. In Canada and the USA labeling of GM food is voluntary, while in Europe all food or feed which contains greater than 0.9% of approved GMOs must be labelled.
Lentiviral vectors in gene therapy is a method by which genes can be inserted, modified, or deleted in organisms using lentiviruses.
Oxitec is a UK-based, US-owned biotechnology company that develops genetically modified insects in order to improve public health and food security through insect control. The insects act as biological insecticides. Insects are controlled without the use of chemical insecticides. Instead, the insects are genetically engineered to be unable to produce offspring. The company claims that this technology is more effective than insecticides and more environmentally friendly.
Margaret M. Perry (1930-2009) was an English molecular geneticist and embryology researcher at the University of Edinburgh whose research produced the first warm-blooded animal developed completely in vitro.
Didier Trono was a Swiss virologist and a professor at the École Polytechnique Fédérale de Lausanne (EPFL). He was known for his research on virus-host interactions and the development of lentiviral vectors for gene therapy.