Artificial Reproductive Technlogies

1.) Artificial insemination (AI) is the process by which sperm is placed into the reproductive tract of a female for the purpose of impregnating the female by using means other than sexual intercourse. In humans, it is used as assisted reproductive technology, primarily to treat infertility but is also increasingly used to enable women without a male partner (i.e., single women and lesbians) to produce children by using sperm provided by a sperm donor. The woman is the gestational and genetic mother of the child produced, and the sperm donor is the genetic or biological father of the child. Specifically, in artificial insemination, freshly ejaculated sperm, or sperm which has been frozen and thawed, is placed in the cervix (intracervical insemination) (ICI)) or in the female's uterus (intrauterine insemination) (IUI) by artificial means. Modern techniques for human artificial insemination were first developed for the dairy cattle industry to allow many cows to be impregnated with the sperm of a bull with traits for improved milk production. Techniques The main techniques used are: •

Intracervical insemination (ICI), the easiest way to inseminate, where semen is injected high into the cervix with a needle-less syringe

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Intrauterine insemination (IUI), where sperm is injected directly into a woman's uterus

Insemination may also be performed into the Fallopian tube although this procedure is no longer generally regarded as having any beneficial effect compared with IUI. See also in vitro fertilisation (IVF) techniques which may involve the use of partner or donor sperm. Intracervical insemination ICI is the easiest way to inseminate, where semen is injected high into the cervix with a needleless syringe. This process most closely replicates the way in which semen is deposited by the penis in the cervix or fornix when the male ejaculates during vaginal intercourse. It is the simplest method of artificial insemination and 'unwashed' or raw semen may be used. It is probably therefore, the most popular method and is used in most home, self and practitoner inseminations. However, more technical procedures may be used which increase the chances of conception. Intrauterine insemination 'Washed sperm', that is, spermatozoa which have been removed from most other components of the seminal fluids, can be injected directly into a woman's uterus in a process called intrauterine insemination (IUI). If the semen is not washed it may elicit uterine cramping, expelling the semen and causing pain, due to content of prostaglandins. (Prostaglandins are also the compounds responsible for causing the myometrium to contract and expel the menses from the uterus, during menstruation.) Intratubal insemination IUI can furthermore be combined with intratubal insemination (ITI), into the Fallopian tube although this procedure is no longer generally regarded as having any beneficial effect compared with IUI. ITI however, should not be confused with gamete intrafallopian transfer, where both eggs and sperm are mixed outside the woman's body and then immediately inserted into the Fallopian tube where fertilization takes place. Artificial insemination in livestock and pets

A breeding mount with built-in artificial vagina used in semen collection from horses for use in artificial insemination Artificial insemination is used in animals to propagate desirable characteristics of one male to many females or overcome breeding problems, particularly in the cases of sheep, horses, cattle, pigs, pedigree dogs, and honeybees. Semen is collected, extended, then cooled or frozen. It can be used on site or shipped to the female's location. If frozen, the small plastic tube holding the semen is referred to as a "straw". To allow the sperm to remain viable during the time before and after it is frozen, the semen is mixed with a solution containing glycerol or other cryoprotectants. An "extender" is a solution that allows the semen from a donor to impregnate more females by making insemination possible with fewer sperm. Antibiotics, such as streptomycin, are sometimes added to the sperm to control some bacterial venereal diseases. Artificial insemination of farm animals is very common in today's agriculture industry in the developed world, especially for breeding dairy cattle (75% of all inseminations) and swine (up to 85% of all inseminations). It provides an economical means for a livestock breeder to improve their herds utilizing males having very desirable traits. Although common with cattle and swine, AI is not as widely practised in the breeding of horses. A small number of equine associations in North America only accept horses that have been conceived by "natural cover" the actual physical mating of a mare to a stallion. The process is widely used allowing the breeding of mares to stallions not resident at the same facility - or even in the same country - through the use of transported frozen or cooled semen. 2.) Cloning in biology is the process of producing populations of genetically-identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments (molecular cloning), cells (cell cloning), or organisms. More generally, the term refers to the production of multiple copies of a product such as digital media or software. Etymology The term clone is derived from κλών, the Greek word for "twig, branch", referring to the process whereby a new plant can be created from a twig. Molecular cloning refers to the process of making multiple copies of a defined DNA sequence. Cloning is frequently used to amplify DNA fragments containing whole genes, but it can also be used to amplify any DNA sequence such as promoters, non-coding sequences and randomly fragmented DNA. It is used in a wide array of biological experiments and practical applications ranging from genetic fingerprinting to large scale protein production. Occasionally, the term cloning is misleadingly used to refer to the identification of the chromosomal location of a gene associated with a particular phenotype of interest, such as in positional cloning. In practice, localization of the gene to a chromosome or genomic region does not necessarily enable one to isolate or amplify the relevant genomic sequence. Cloning a cell means to derive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. However, in the case of cell cultures from multi-cellular organisms, cell cloning is an arduous task as these cells will not readily grow in standard media. Somatic cell nuclear transfer can also be used to create a clonal embryo. The most likely purpose for this is to produce embryos for use in research, particularly stem cell research. This process is also called "research cloning" or "therapeutic cloning." The goal is not to create cloned human beings, but rather to harvest stem cells that can be used to study human

development and to potentially treat disease. While a clonal human blastocyst has been created, stem cell lines are yet to be isolated from a clonal source. Organism cloning refers to the procedure of creating a new multicellular organism, genetically identical to another. In essence this form of cloning is an asexual method of reproduction, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a naturally occurring phenomenon in many species, including most plants (see vegetative reproduction) and some insects. Horticultural The term clone is used in horticulture to mean all descendants of a single plant, produced by vegetative reproduction or apomixis. Many horticultural plant cultivars are clones, having been derived from a single individual, multiplied by some process other than sexual reproduction. As an example, some European cultivars of grapes represent clones that have been propagated for over two millennia. Other examples are potato and banana. Grafting can be regarded as cloning, since all the shoots and branches coming from the graft are genetically a clone of a single individual, but this particular kind of cloning has not come under ethical scrutiny and is generally treated as an entirely different kind of operation. Many trees, shrubs, vines, ferns and other herbaceous perennials form clonal colonies. Parts of a large clonal colony often become detached from the parent, termed fragmentation, to form separate individuals. Some plants also form seeds asexually, termed apomixis, e.g. dandelion. Parthenogenesis Clonal derivation exists in nature in some animal species and is referred to as parthenogenesis (reproduction of an organism by itself without a mate). An example is the "Little Fire Ant" (Wasmannia auropunctata), which is native to Central and South America but has spread throughout many tropical environments. Reproductive cloning Reproductive cloning uses "somatic cell nuclear transfer" (SCNT) to create animals that are genetically identical. This process entails the transfer of a nucleus from a donor adult cell (somatic cell) to an egg which has no nucleus. If the egg begins to divide normally it is transferred into the uterus of the surrogate mother. Such clones are not strictly identical since the somatic cells may contain mutations in their nuclear DNA. Additionally, the mitochondria in the cytoplasm also contains DNA and during SCNT this DNA is wholly from the donor egg, thus the mitochondrial genome is not the same as that of the nucleus donor cell from which it was produced. This may have important implications for cross-species nuclear transfer in which nuclear-mitochondrial incompatibilities may lead to death. 3. Cryopreservation is a process where cells or whole tissues are preserved by cooling to low sub-zero temperatures, such as (typically) 77 K or −196 °C (the boiling point of liquid nitrogen). At these low temperatures, any biological activity, including the biochemical reactions that would lead to cell death, is effectively stopped. However, when vitrification solutions are not used, the cells being preserved are often damaged due to freezing during the approach to low temperatures or warming to room temperature.

Phenomena which can cause damage to cells during cryopreservation are solution effects, extracellular ice formation, dehydration and intracellular ice formation. Many of these effects can be reduced by cryoprotectants.

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Semen (which can be used successfully almost indefinitely after cryopreservation),

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Blood (special cells for transfusion, or stem cells)

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Tissue samples like tumors and histological cross sections

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Human eggs (oocytes)

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Human embryos that are 2, 4 or 8 cells

4. Embryo transfer refers to a step in the process of in vitro fertilization (IVF) whereby one or several embryos are placed into the uterus of the female with the intent to establish a pregnancy. Fresh versus frozen Embryos can be either "fresh" from fertilized egg cells of the same menstrual cycle, or "frozen", that is they have been generated in a preceding cycle, cryopreserved and are thawed just prior to the transfer. Babies born from frozen IVF embryos are less likely to be born prematurely or underweight than are those conceived during fresh treatment cycles, three independent teams of scientists have found. One of the studies also recorded lower rates of stillbirth and early death among frozen-embryo babies. The results, from researchers based in the United States, Australia and Finland, suggest that far from being riskier than conventional IVF, as is generally thought, cycles using frozen embryos may actually be safer, Mark Henderson of the Times London reported in November 2008. Embryo number A major issue is how many embryos should be transferred. Placement of multiple embryos carries the risk of multiple pregnancy. In the past, physicians have often placed too many embryos in the hope to establish a pregnancy. However, the rise in multiple pregnancies has led to a reassessment of this approach. Professional societies and in many countries, the legislature, have issued guidelines or laws to curtail a practice of placing too many embryos in an attempt to reduce multiple pregnancies. e-SET The technique of selecting only one embryo to transfer to the woman is called elective-Single Embryo Transfer (e-SET). It lowers the risk of multiple pregnancies, compared with e.g. Double Embryo Transfer (DET). Follow-up After embryo transfer patients are kept on estrogen and progesterone medication; pregnancy testing is done typically two weeks after the transfer The first transfer of an embryo from one human to another resulting in pregnancy was reported in July 1983 and subsequently led to the announcement of the first human birth February 3, 1984. This procedure was performed at the Harbor UCLA Medical Center under the direction of Dr. John Buster and the University of California at Los Angeles School of Medicine.

5. In vitro fertilisation (IVF) is a process by which egg cells are fertilized by sperm outside of the womb, in vitro. IVF is a major treatment in infertility when other methods of assisted reproductive technology have failed. The process involves hormonally controlling the ovulatory process, removing ova (eggs) from the woman's ovaries and letting sperm fertilise them in a fluid medium. The fertilized egg (zygote) is then transferred to the patient's uterus with the intent to establish a successful pregnancy. The first test tube baby was born in 1978. The term in vitro, from the Latin root meaning within the glass, is used, because early biological experiments involving cultivation of tissues outside the living organism from which they came, were carried out in glass containers such as beakers, test tubes, or petri dishes. Today, the term in vitro is used to refer to any biological procedure that is performed outside the organism it would normally be occurring in, to distinguish it from an in vivo procedure, where the tissue remains inside the living organism within which it is normally found. A colloquial term for babies conceived as the result of IVF, test tube babies, refers to the tube-shaped containers of glass or plastic resin, called test tubes,that are commonly used in chemistry labs and biology labs. However in vitro fertilisation is usually performed in the shallower containers called Petri dishes. (Petri-dishes may also be made of plastic resins.) However, the IVF method of Autologous Endometrial Coculture is actually performed on organic material, but is yet called in vitro. This is used when parents are having infertility problems or they want to have multiple births. Indications Initially IVF was developed to overcome infertility due to problems of the fallopian tube, but it turned out that it was successful in many other infertility situations as well. The introduction of intracytoplasmic sperm injection (ICSI) addresses the problem of male infertility to a large extent. For IVF to be successful it may be easier to say that it requires healthy ova, sperm that can fertilise, and a uterus that can maintain a pregnancy. Due to the costs of the procedure, IVF is generally attempted only once other, less expensive, options have failed. This means that IVF can be used for females who have already gone through menopause. The donated oocyte can be fertilised in a crucible. If the fertilisation is successful, the zygote will be transferred into the uterus, within which it will develop into an embryo. John Rock was the first to extract an intact fertilised egg. 6. Surrogacy is a method of reproduction whereby a woman agrees to become pregnant and deliver a child for a contracted party. She may be the child's genetic mother (the more traditional form of surrogacy), or she may, as a gestational carrier, carry the pregnancy to delivery after having been implanted with an embryo, in some jurisdictions an illegal medical procedure. A surrogate mother is the woman who is pregnant with the child and intends to relinquish it after birth. The word surrogate, from Latin subrŏgare (to substitute), means appointed to act in the place of the intended parents. The intended parent(s) is the individual or couple who intends to rear the child after its birth. In traditional surrogacy (also known as the Straight method) the surrogate is pregnant with her own biological child, but this child was conceived with the intention of relinquishing the child to be raised by others such as the biological father and possibly his spouse or partner, either male or female. The child may be conceived via home artificial insemination using fresh or frozen sperm or impregnated via IUI (intrauterine insemination), or ICI (intra cervical insemination) which is performed at a fertility clinic. Sperm from the male partner of the 'commissioning couple' may be used, or alternatively, sperm from a sperm donor can be

used. Donor sperm will, for example, be used if the 'commissioning couple' are both female and where the child is commissioned by a single woman. In gestational surrogacy (aka the Host method) the surrogate becomes pregnant via embryo transfer with a child of which she is not the biological mother. She may have made an arrangement to relinquish it to the biological mother or father to raise, or to a parent who is unrelated to the child (e. g. because the child was conceived using egg donation, sperm donation or is the result of a donated embryo). The surrogate mother may be called the gestational carrier. Altruistic surrogacy is a situation where the surrogate receives no financial reward for her pregnancy or the relinquishment of the child (although usually all expenses related to the pregnancy and birth are paid by the intended parents such as medical expenses, maternity clothing, and other related expenses).[1] Commercial surrogacy is a form of surrogacy in which a gestational carrier is paid to carry a child to maturity in her womb and is usually resorted to by well off infertile couples who can afford the cost involved or people who save and borrow in order to complete their dream of being parents. This procedure is legal in several countries including in India where due to excellent medical infrastructure, high international demand and ready availability of poor surrogates it is reaching industry proportions. Commercial surrogacy is sometimes referred to by the emotionally charged and potentially offensive terms "wombs for rent", "outsourced pregnancies" or "baby farms".