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), including animals, plants, and microorganisms.
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.
Gene therapy is a medical technology that aims to produce a therapeutic effect through the manipulation of gene expression or through altering the biological properties of living cells.
In genetics and developmental biology, somatic cell nuclear transfer (SCNT) is a laboratory strategy for creating a viable embryo from a body cell and an egg cell. The technique consists of taking a denucleated oocyte and implanting a donor nucleus from a somatic (body) cell. It is used in both therapeutic and reproductive cloning. In 1996, Dolly the sheep became famous for being the first successful case of the reproductive cloning of a mammal. In January 2018, a team of scientists in Shanghai announced the successful cloning of two female crab-eating macaques from foetal nuclei.
The term modifications in genetics refers to both naturally occurring and engineered changes in DNA. Incidental, or natural mutations occur through errors during replication and repair, either spontaneously or due to environmental stressors. Intentional modifications are done in a laboratory for various purposes, developing hardier seeds and plants, and increasingly to treat human disease. The use of gene editing technology remains controversial.
A designer baby is a baby whose genetic makeup has been selected or altered, often to exclude a particular gene or to remove genes associated with disease. This process usually involves analysing a wide range of human embryos to identify genes associated with particular diseases and characteristics, and selecting embryos that have the desired genetic makeup; a process known as preimplantation genetic diagnosis. Screening for single genes is commonly practiced, and polygenic screening is offered by a few companies. Other methods by which a baby's genetic information can be altered involve directly editing the genome before birth, which is not routinely performed and only one instance of this is known to have occurred as of 2019, where Chinese twins Lulu and Nana were edited as embryos, causing widespread criticism.
The historical application of biotechnology throughout time is provided below in chronological order.
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.
Ming-Ming Zhou is an American scientist whose specification is structural and chemical biology, NMR spectroscopy, and drug design. He is the Dr. Harold and Golden Lamport Professor and Chairman of the Department of Pharmacological Sciences. He is also the co-director of the Drug Discovery Institute at the Icahn School of Medicine at Mount Sinai and Mount Sinai Health System in New York City, as well as Professor of Sciences. Zhou is an elected fellow of the American Association for the Advancement of Science.
Forkhead box protein J1 is a protein that in humans is encoded by the FOXJ1 gene. It is a member of the Forkhead/winged helix (FOX) family of transcription factors that is involved in ciliogenesis. FOXJ1 is expressed in ciliated cells of the lung, choroid plexus, reproductive tract, embryonic kidney and pre-somite embryo stage.
Shoukhrat Mitalipov is an American biologist who heads the Center for Embryonic Cell and Gene Therapy at the Oregon Health & Science University in Portland. He is a well known pioneer of many nuclear transplantation studies and was named in 2013 by journal Nature as "the cloning chief". Mitalipov is also a godfather of a gene therapy, known as mitochondrial replacement therapy, that prevents inheritance of mitochondrial diseases. He discovered a new way of creating human stem cells from skin cells.
NgAgo is a single-stranded DNA (ssDNA)-guided Argonaute endonuclease, an acronym for NatronobacteriumgregoryiArgonaute. NgAgo binds 5′ phosphorylated ssDNA of ~24 nucleotides (gDNA) to guide it to its target site and will make DNA double-strand breaks at the gDNA site. Like the CRISPR/Cas system, NgAgo was reported by Chunyu Han et al. to be suitable for genome editing, but this has not been replicated. In contrast to Cas9, the NgAgo–gDNA system does not require a protospacer adjacent motif (PAM).
John Jin Zhang is a medical scientist who has made contributions in fertility research, and particularly in in vitro fertilization. He made headlines in September 2016 for successfully producing the world's first three-parent baby using the spindle transfer technique of mitochondrial replacement. Having obtained an M.D. from Zhejiang University School of Medicine, an M.Sc. from University of Birmingham, and a Ph.D. from University of Cambridge, he became the founder-director of New Hope Fertility Center in New York, USA.
Human germline engineering is the process by which the genome of an individual is edited in such a way that the change is heritable. This is achieved by altering the genes of the germ cells, which then mature into genetically modified eggs and sperm. For safety, ethical, and social reasons, there is broad agreement among the scientific community and the public that germline editing for reproduction is a red line that should not be crossed at this point in time. There are differing public sentiments, however, on whether it may be performed in the future depending on whether the intent would be therapeutic or non-therapeutic.
Zhong Zhong and Hua Hua are a pair of identical crab-eating macaques that were created through somatic cell nuclear transfer (SCNT), the same cloning technique that produced Dolly the sheep in 1996. They are the first cloned primates produced by this technique. Unlike previous attempts to clone monkeys, the donated nuclei came from fetal cells, not embryonic cells. The primates were born from two independent surrogate pregnancies at the Institute of Neuroscience of the Chinese Academy of Sciences in Shanghai.
Ru-Chih Chow Huang is a Taiwanese-American biology professor at Johns Hopkins University. She is a biochemist who worked with James F. Bonner and Doug Fambrough to characterize and discern functions for nuclear histones in the early 1960s when the field lacked a consensus on types and functions of individual histone proteins. Later she made discoveries about the molecular biology of cancer and of viral gene regulation.
The He Jiankui affair is a scientific and bioethical controversy concerning the use of genome editing following its first use on humans by Chinese scientist He Jiankui, who edited the genomes of human embryos in 2018. He became widely known on 26 November 2018 after he announced that he had created the first human genetically edited babies. He was listed in Time magazine's 100 most influential people of 2019. The affair led to ethical and legal controversies, resulting in the indictment of He and two of his collaborators, Zhang Renli and Qin Jinzhou. He eventually received widespread international condemnation.
He Jiankui is a Chinese biophysicist who was an associate professor in the Department of Biology of the Southern University of Science and Technology (SUSTech) in Shenzhen, China. Earning his Ph.D. from Rice University in Texas on protein evolution, including that of CRISPR, He learned gene-editing techniques (CRISPR/Cas9) as a postdoctoral researcher at Stanford University in California.
CRISPR gene editing is a genetic engineering technique in molecular biology by which the genomes of living organisms may be modified. It is based on a simplified version of the bacterial CRISPR-Cas9 antiviral defense system. By delivering the Cas9 nuclease complexed with a synthetic guide RNA (gRNA) into a cell, the cell's genome can be cut at a desired location, allowing existing genes to be removed and/or new ones added in vivo.
LEAPER is a genetic engineering technique in molecular biology by which RNA can be edited. The technique relies on engineered strands of RNA to recruit native ADAR enzymes to swap out different compounds in RNA. Developed by researchers at Peking University in 2019, the technique, some have claimed, is more efficient than the CRISPR gene editing technique. Initial studies have claimed that editing efficiencies of up to 80%.
