StemCell Therapy

Also called: precision medicine or individualized medicine(Showmore)

personalized medicine, field of medicine in which decisions concerning disease prevention, diagnosis, and treatment are tailored to individual patients based on information derived from genetic and genomic data. Personalized medicine centres on the concept that information about a patients genes and genome allows physicians to make more informed and effective decisions about a patients care.This idea essentially is an extension of conventional medicine, in which one strategy is applied across all patients, without tailoring to personal genetic and genomic information.

The concept of personalized medicine, although not novel at the time, materialized in the 1990s, following advances in DNA sequencing technology, including automation and increased throughput. Out of those advances came efforts such as the Human Genome Project (HGP; 19902003), in which sequences of more than three billion base pairs of the human genome were elucidated and made available to researchers worldwide. Likewise, the International HapMap Project (200210), which identified genetic variations that contribute tohuman disease, provided researchers with the information needed to associate gene variants with specific diseases and disorders.

Those advances cast light on phenomena in medicine that had been observed for yearsfor example, that certain drugs are more effective in some patients and that, in response to certain medications, some patients experience unusually severe side effects. Progress in understanding the molecular factors underlying the influence of individual genetic constitution on disease and therapeutics was greatly aided by developments in pharmacogenetics and pharmacogenomicsthe study of genetic causes behind differences in how individuals respond to drugs and the study of how multiple variations within the genome affect responses to drug treatments, respectively. Using data derived from pharmacogenetics and pharmacogenomics, researchers were able to develop more objective and accurate tests fordisease diagnosis and for predicting how patients would respond to therapeutic agents. In some cases, researchers found, using genetic and other molecular data to inform diagnosis and treatment, that the development or outcome of certain diseases could be modified.

The emergence of personalized medicine was further facilitated by developments in the area of health information technology, which entails electronic processing and storage of patient data, and in the clinical uptake of personalized medicine, particularly through translational and clinical research. Advances in those areasespecially the implementation of electronic health records (EHRs), which store data on patient history, medications, test results, anddemographicswere critical to the integration of data derived from genetics and genomics research and clinical settings.

Personalized medicine is used in various ways to facilitate the prevention, diagnosis, and treatment of disease. For example, physicians can use information on family history of disease to assess a patients risk for a disease. In certain instances, family history can be used to determine whether a patient should undergo genetic testing and, based on that information, whether the individual would benefit from specific preventive measures. In the case of individuals with a family history of Lynch syndrome (a cause of hereditary colorectal cancer), for instance, detection of the causative mutation through genetic testing can be used to inform decisions about screening. For persons who carry the mutation, frequent and routine screening for evidence of precancerous lesions in the colon allows for early disease detection, which can be a lifesaving measure. Similarly, tests capable of detecting mutations in multiple genes at one time can assist in the early diagnosis of hereditary forms of breast cancer, ovarian cancer, and prostate cancer.

The term personalized medicine is sometimes considered to be synonymous with targeted therapy, a form of treatment centred on the use of drugs that target specific molecules involved in regulating the growth and spread of cancer.Among the first successful targeted therapies was the anticancerdrug imatinib, which istailored to patients with chronic myelogenousleukemia(CML) who carry anenzymecalled BCR-ABLtyrosinekinase, a protein produced by a cytogenetic abnormality known as the Philadelphiachromosome. Imatinib blocks the proliferation of CML cells that possess themutated kinase, effectively reversing the abnoramalitys cancerous effects.

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Another example of personalized medicine applied to therapeutics is the use of genotyping to identify variations in enzymes that alter a patients sensitivity to the commonly prescribed anticoagulant drug warfarin. Information about variations in warfarin-metabolizing enzymes can be used to help guide decisions about the amount of the drug that a patient needs to receive in order to achieve the desired effect.

Personalized medicine faces significant challenges. For example, compared with the HGP reference sequence of the human genome, each individual persons genome houses roughly three to five million variations. Thus, attributing disease causation or therapeutic response to a given genetic variant requires careful analysis and interpretation across multiple disciplines. Moreover, genomes vary across geographic and ethnic populations and are influenced by environmental factors; thus, an individual variation identified within a given population may have very different impacts on disease in another population, based on ethnic or geographic factors.

Technological issues also continue to challenge advances in personalized medicine. The structure of EHR data, for example, can impact its utility. Access to and analysis of genomic data in EHRs may be limited by the presentation of genomic test results as a summary that includes relevant observations but excludes raw data and by the lack of information on details such as patient lifestyle and behaviour, which are essential to the accurateinterpretation of genomic information.

Various ethical issues are associated with personalized medicine. Of particular concern is that the majority of genomic studies historically have focused on populations of European descent, with significant underrepresentation of racial and ethnic minorities. This unevenness in representation can impact algorithms used to guide decisions about drug selection and dosing regimens, potentially resulting in ineffective treatment and poorer outcomes for patients whose genetic backgrounds and lifestyles differ from more thoroughly studied groups.

Other ethical issues surround privacy and security concerns, mainly involving the use of EHRs. For example, a breachin an EHR system could result in the release of personal information and health data as well as information about health care providers.Personalized medicine also carries high costs and therefore is potentially inaccessible for patients who lack health insurance and financially out of reach for less-developed countries with limited health resources.

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Personalized medicine | Definition, Origins, Examples, & Ethical ...

USES AND APPLICATIONS OF BIOTECHNOLOGY

Biotechnological innovations are already part of our daily lives and we find them in pharmacies and supermarkets, among many other places. In addition, they were of key importance during the fight against the COVID-19 pandemic as they helped decipher the genome of the virus and in understanding how our body's defence mechanism works against infectious agents.

Biotechnology will therefore play a crucial role in the society of the future in preventing and containing potential pathogens. But this is just one of its many applications... Below, we review some of the most relevant in different fields:

The development of insulin, the growth hormone, molecular identity and diagnostics, gene therapies and vaccines such as hepatitis B are some of the milestones of biotechnology and its alliance with genetic engineering. In addition, it is also used in the diagnosis of diseases due to its ability to perform very complicated tests in a shorter time and at lower cost.

The revolution of the new smart materials hand-in-hand with biotechnology has only just begun, with the main advantage that it can make easily degradable products. Such products help the environment because they generate less waste at the time of destruction, as is the case with biodegradable plastics.

In addition to the genetically modified foods mentioned above, thanks to biotechnology products such as WEMA have been created, a type of crop resistant to droughts and certain insects that may prove essential in fighting hunger in Africa.

Through bioremediation processes, very useful for ecological recovery, the catabolic properties of microorganisms, fungi, plants and enzymes are used to restore contaminated ecosystems.

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What is Biotechnology? Types and Applications - Iberdrola

Are GMOs Safe? The Benefits of Science-Enhanced Foods | TIME  TIME

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Are GMOs Safe? The Benefits of Science-Enhanced Foods | TIME - TIME

human genetics, study of the inheritance of characteristics by children from parents. Inheritance in humans does not differ in any fundamental way from that in other organisms.

The study of human heredity occupies a central position in genetics. Much of this interest stems from a basic desire to know who humans are and why they are as they are. At a more practical level, an understanding of human heredity is of critical importance in the prediction, diagnosis, and treatment of diseases that have a genetic component. The quest to determine the genetic basis of human health has given rise to the field of medical genetics. In general, medicine has given focus and purpose to human genetics, so the terms medical genetics and human genetics are often considered synonymous.

A new era in cytogenetics, the field of investigation concerned with studies of the chromosomes, began in 1956 with the discovery by Jo Hin Tjio and Albert Levan that human somatic cells contain 23 pairs of chromosomes. Since that time the field has advanced with amazing rapidity and has demonstrated that human chromosome aberrations rank as major causes of fetal death and of tragic human diseases, many of which are accompanied by intellectual disability. Since the chromosomes can be delineated only during mitosis, it is necessary to examine material in which there are many dividing cells. This can usually be accomplished by culturing cells from the blood or skin, since only the bone marrow cells (not readily sampled except during serious bone marrow disease such as leukemia) have sufficient mitoses in the absence of artificial culture. After growth, the cells are fixed on slides and then stained with a variety of DNA-specific stains that permit the delineation and identification of the chromosomes. The Denver system of chromosome classification, established in 1959, identified the chromosomes by their length and the position of the centromeres. Since then the method has been improved by the use of special staining techniques that impart unique light and dark bands to each chromosome. These bands permit the identification of chromosomal regions that are duplicated, missing, or transposed to other chromosomes.

Micrographs showing the karyotypes (i.e., the physical appearance of the chromosome) of a male and a female have been produced. In a typical micrograph the 46 human chromosomes (the diploid number) are arranged in homologous pairs, each consisting of one maternally derived and one paternally derived member. The chromosomes are all numbered except for the X and the Y chromosomes, which are the sex chromosomes. In humans, as in all mammals, the normal female has two X chromosomes and the normal male has one X chromosome and one Y chromosome. The female is thus the homogametic sex, as all her gametes normally have one X chromosome. The male is heterogametic, as he produces two types of gametesone type containing an X chromosome and the other containing a Y chromosome. There is good evidence that the Y chromosome in humans, unlike that in Drosophila, is necessary (but not sufficient) for maleness.

Britannica Quiz

Genetics Quiz

A human individual arises through the union of two cells, an egg from the mother and a sperm from the father. Human egg cells are barely visible to the naked eye. They are shed, usually one at a time, from the ovary into the oviducts (fallopian tubes), through which they pass into the uterus. Fertilization, the penetration of an egg by a sperm, occurs in the oviducts. This is the main event of sexual reproduction and determines the genetic constitution of the new individual.

Human sex determination is a genetic process that depends basically on the presence of the Y chromosome in the fertilized egg. This chromosome stimulates a change in the undifferentiated gonad into that of the male (a testicle). The gonadal action of the Y chromosome is mediated by a gene located near the centromere; this gene codes for the production of a cell surface molecule called the H-Y antigen. Further development of the anatomic structures, both internal and external, that are associated with maleness is controlled by hormones produced by the testicle. The sex of an individual can be thought of in three different contexts: chromosomal sex, gonadal sex, and anatomic sex. Discrepancies between these, especially the latter two, result in the development of individuals with ambiguous sex, often called hermaphrodites. Homosexuality is unrelated to the above sex-determining factors. It is of interest that in the absence of a male gonad (testicle) the internal and external sex anatomy is always female, even in the absence of a female ovary. A female without ovaries will, of course, be infertile and will not experience any of the female developmental changes normally associated with puberty. Such a female will often have Turner syndrome.

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If X-containing and Y-containing sperm are produced in equal numbers, then according to simple chance one would expect the sex ratio at conception (fertilization) to be half boys and half girls, or 1 : 1. Direct observation of sex ratios among newly fertilized human eggs is not yet feasible, and sex-ratio data are usually collected at the time of birth. In almost all human populations of newborns, there is a slight excess of males; about 106 boys are born for every100 girls. Throughout life, however, there is a slightly greater mortality of males; this slowly alters the sex ratio until, beyond the age of about 50 years, there is an excess of females. Studies indicate that male embryos suffer a relatively greater degree of prenatal mortality, so the sex ratio at conception might be expected to favour males even more than the 106 : 100 ratio observed at birth would suggest. Firm explanations for the apparent excess of male conceptions have not been established; it is possible that Y-containing sperm survive better within the female reproductive tract, or they may be a little more successful in reaching the egg in order to fertilize it. In any case, the sex differences are small, the statistical expectation for a boy (or girl) at any single birth still being close to one out of two.

During gestationthe period of nine months between fertilization and the birth of the infanta remarkable series of developmental changes occur. Through the process of mitosis, the total number of cells changes from 1 (the fertilized egg) to about 2 1011. In addition, these cells differentiate into hundreds of different types with specific functions (liver cells, nerve cells, muscle cells, etc.). A multitude of regulatory processes, both genetically and environmentally controlled, accomplish this differentiation. Elucidation of the exquisite timing of these processes remains one of the great challenges of human biology.

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Human genetics | Description, Chromosomes, & Inheritance

Reviewed by James Langeland, Professor, Kalamazoo College on 1/30/23

Comprehensivenessrating:4see less

This text does what it claims to do. It provides an introductory overview of a broad swath of genetics.

Content Accuracyrating:4

No glaring errors. One could always nitpick any text book.

Relevance/Longevityrating:3

The text is relevant, but not particularly unique in any sense. One could find virtually the same information in any number of genetics textbooks, presented in largely the same way. A major problem here is that the filed is presented more or less historically with many of the experiments and concepts being described having little to no relevance to genetics today. This is a problem with many texts so I do not single this one out.

Clarityrating:4

As with many open source texts, this one suffers from substandard figures, which directly influences clarity. The words on the age are fine, but the adage is true-a picture can be worth a thousand words. The mainstream publishers spent a lot of money on figures and it shows--they can be really good.

Consistencyrating:4

No comments here.

Modularityrating:4

There seem to be appropriate and logical chapter and section breaks.

Organization/Structure/Flowrating:3

The flow is the same as nearly any other genetics textbook. It suffers from a rigid historical framework. Better than most at Muller's morphs however!

Interfacerating:5

No problems here. I do really like the integrated you tube links. I did not dive into the content of those videos (beyond the scope of my review), but the fact that they are there in abundance is a good use of the open source approach.

Grammatical Errorsrating:5

No problems here.

Cultural Relevancerating:3

No comment.

A very timely section on SARS-Cov-2 at the end! Rich with study questions and answers. Genetics is and should be very problem based, so this is good.I appreciate what is being offered here and I understand the market. There is nothing "wrong" with this textbook. There is also no wow factor that would cause me to adopt it at this time.

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Introduction to Genetics - Open Textbook Library