GENETICS
a science that studies heredity and variability - properties inherent in all living organisms. The endless variety of species of plants, animals and microorganisms is supported by the fact that each species retains its characteristic features over generations: in the cold North and in hot countries, a cow always gives birth to a calf, a hen breeds chicks, and wheat reproduces wheat. At the same time, living beings are individual: all people are different, all cats are somehow different from each other, and even ears of wheat, if you look at them more closely, have their own characteristics. These two most important properties of living beings - to be similar to their parents and to be different from them - constitute the essence of the concepts of “heredity” and “variability”. The origins of genetics, like any other science, should be sought in practice. Since people started breeding animals and plants, they began to understand that the characteristics of offspring depend on the properties of their parents. By selecting and crossing the best individuals, man from generation to generation created animal breeds and plant varieties with improved properties. The rapid development of breeding and plant growing in the second half of the 20th century. gave rise to increased interest in the analysis of the phenomenon of heredity. At that time, it was believed that the material substrate of heredity is a homogeneous substance, and the hereditary substances of parental forms are mixed in the offspring in the same way as mutually soluble liquids are mixed with each other. It was also believed that in animals and humans the substance of heredity is somehow connected with blood: the expressions “half-breed”, “purebred”, etc. have survived to this day. It is not surprising that contemporaries did not pay attention to the results of the work of the abbot of the monastery in Brno, Gregor Mendel, on crossing peas. None of those who listened to Mendel's report at a meeting of the Society of Naturalists and Physicians in 1865 were able to unravel the fundamental biological laws in some "strange" quantitative relationships discovered by Mendel when analyzing pea hybrids, and in the person who discovered them, the founder of a new science - genetics. After 35 years of oblivion, Mendel's work was appreciated: his laws were rediscovered in 1900, and his name entered the history of science. The laws of genetics, discovered by Mendel, Morgan and a galaxy of their followers, describe the transmission of traits from parents to children. They argue that all heritable traits are determined by genes. Each gene can be present in one or more forms, called alleles. All cells of the body, except sex cells, contain two alleles of each gene, i.e. are diploid. If two alleles are identical, the organism is said to be homozygous for that gene. If the alleles are different, the organism is called heterozygous. Cells involved in sexual reproduction (gametes) contain only one allele of each gene, i.e. they are haploid. Half of the gametes produced by an individual carry one allele, and half carry the other. The union of two haploid gametes during fertilization results in the formation of a diploid zygote, which develops into an adult organism. Genes are specific pieces of DNA; they are organized into chromosomes located in the cell nucleus. Each type of plant or animal has a certain number of chromosomes. In diploid organisms, the number of chromosomes is paired; two chromosomes of each pair are called homologous. Let's say a person has 23 pairs of chromosomes, with one homologue of each chromosome obtained from the mother and the other from the father. There are also extranuclear genes (in mitochondria, and in plants, also in chloroplasts). Features of the transmission of hereditary information are determined by intracellular processes: mitosis and meiosis. Mitosis is the process of distributing chromosomes to daughter cells during cell division. As a result of mitosis, each chromosome of the parent cell is duplicated and identical copies disperse to the daughter cells; in this case, hereditary information is completely transmitted from one cell to two daughter cells. This is how cell division occurs in ontogenesis, i.e. process of individual development. Meiosis is a specific form of cell division that occurs only during the formation of sex cells, or gametes (sperm and eggs). Unlike mitosis, the number of chromosomes during meiosis is halved; each daughter cell receives only one of the two homologous chromosomes of each pair, so that in half of the daughter cells there is one homologue, in the other half - another; in this case, chromosomes are distributed in gametes independently of each other. (The genes of mitochondria and chloroplasts do not follow the law of equal distribution during division.) When two haploid gametes merge (fertilization), the number of chromosomes is restored again - a diploid zygote is formed, which received a single set of chromosomes from each parent.
Methodological approaches. Thanks to what features of Mendel's methodological approach was he able to make his discoveries? For his crossing experiments, he chose pea lines that differed in one alternative trait (seeds are smooth or wrinkled, cotyledons are yellow or green, the shape of the bean is convex or constricted, etc.). He analyzed the offspring from each cross quantitatively, i.e. counted the number of plants with these characteristics, which no one had done before. Thanks to this approach (the selection of qualitatively different characteristics), which formed the basis for all subsequent genetic research, Mendel showed that the characteristics of parents are not mixed in offspring, but are passed on unchanged from generation to generation. Mendel's merit also lies in the fact that he gave geneticists a powerful method for studying hereditary characteristics - hybridological analysis, i.e. a method of studying genes by analyzing the characteristics of the descendants of certain crosses. Mendel's laws and hybridological analysis are based on events occurring in meiosis: alternative alleles are found on homologous chromosomes of hybrids and therefore diverge equally. It is the hybridological analysis that determines the requirements for objects of general genetic research: these must be easily cultivated organisms that produce numerous offspring and have a short reproductive period. Among higher organisms, these requirements are met by the fruit fly Drosophila melanogaster. For many years it became a favorite object of genetic research. Through the efforts of geneticists from different countries, fundamental genetic phenomena were discovered. It was found that genes are located linearly on chromosomes and their distribution in descendants depends on the processes of meiosis; that genes located on the same chromosome are inherited together (gene linkage) and are subject to recombination (crossing over). Genes localized in sex chromosomes have been discovered, the nature of their inheritance has been established, and the genetic basis of sex determination has been identified. It has also been discovered that genes are not immutable, but are subject to mutation; that a gene is a complex structure and there are many forms (alleles) of the same gene. Then microorganisms became the object of more scrupulous genetic research, in which the molecular mechanisms of heredity began to be studied. Thus, the phenomenon of bacterial transformation was discovered in Escherichia coli - the inclusion of DNA belonging to a donor cell into a recipient cell - and for the first time it was proven that DNA is the carrier of genes. The structure of DNA was discovered, the genetic code was deciphered, the molecular mechanisms of mutations, recombination, genomic rearrangements were revealed, the regulation of gene activity, the phenomenon of movement of genome elements, etc. were studied.
See CELL;
HERITAGE;
MOLECULAR BIOLOGY.
Along with these model organisms, genetic studies were carried out on many other species, and the universality of the basic genetic mechanisms and methods for studying them was shown for all organisms - from viruses to humans.
Achievements and problems of modern genetics. Based on genetic research, new fields of knowledge (molecular biology, molecular genetics), corresponding biotechnologies (such as genetic engineering) and methods (for example, polymerase chain reaction) have emerged that make it possible to isolate and synthesize nucleotide sequences, integrate them into the genome, and obtain hybrid DNA with properties that did not exist in nature. Many drugs have been obtained, without which medicine is no longer conceivable.
(see GENETIC ENGINEERING).
Principles for breeding transgenic plants and animals with characteristics of different species have been developed. It has become possible to characterize individuals using many polymorphic DNA markers: microsatellites, nucleotide sequences, etc. Most molecular biological methods do not require hybridological analysis. However, for trait research, marker analysis and gene mapping, this classical genetics method is still needed. Like any other science, genetics has been and remains a weapon of unscrupulous scientists and politicians. Its branch, such as eugenics, according to which a person’s development is completely determined by his genotype, served as the basis for the creation of racial theories and sterilization programs in the 1930-1960s. On the contrary, the denial of the role of genes and the acceptance of the idea of the dominant role of the environment led to the cessation of genetic research in the USSR from the late 1940s to the mid-1960s. Nowadays, environmental and ethical problems arise in connection with work on the creation of “chimeras” - transgenic plants and animals, “copying” animals by transplanting the cell nucleus into a fertilized egg, genetic “certification” of people, etc. The leading powers of the world are passing laws aimed at preventing the undesirable consequences of such work. Modern genetics has provided new opportunities for studying the activity of the body: with the help of induced mutations, you can turn off and turn on almost any physiological processes, interrupt the biosynthesis of proteins in the cell, change morphogenesis, and stop development at a certain stage. We can now explore population and evolutionary processes deeper
(see POPULATION GENETICS),
study hereditary diseases
(see GENETIC COUNSELING)
the problem of cancer and much more. In recent years, the rapid development of molecular biological approaches and methods has allowed geneticists not only to decipher the genomes of many organisms, but also to design living beings with specified properties. Thus, genetics opens up ways to model biological processes and contributes to the fact that biology, after a long period of fragmentation into separate disciplines, enters the era of unification and synthesis of knowledge.
LITERATURE
Ayala F., Caiger J. Modern genetics, vols. 1-3. M., 1988 Singer M., Berg P. Genes and genomes, vol. 1-2. M., 1998
Collier's Encyclopedia. - Open Society. 2000 .
Synonyms:See what “GENETICS” is in other dictionaries:
GENETICS- (from the Greek genesis origin), usually defined as the physiology of variability and heredity. This is exactly how Bateson defined the content of genetics, who proposed this term in 1906, wanting to emphasize that of the three main elements ... Great Medical Encyclopedia
- (from the Greek genesis origin), the science of heredity and variability of living organisms and methods of managing them. It is based on the patterns of heredity discovered by G. Mendel when crossing different types. varieties of peas (1865), as well as... ... Biological encyclopedic dictionary
- [gr. genetikos relating to birth, origin] biol. a branch of biology that studies the laws of heredity and variability of organisms. Dictionary of foreign words. Komlev N.G., 2006. genetics (gr. genetikos relating to birth, origin)… … Dictionary of foreign words of the Russian language
Corrupt girl of imperialism Dictionary of Russian synonyms. genetics noun, number of synonyms: 11 biology (73) ... Dictionary of synonyms
- (Greek genetikos - related to origin) the science of the laws of heredity and variability of organisms. Genetics occupies one of the central places in the complex of biological disciplines; its object is a genotype that performs the function... ... Encyclopedia of Cultural Studies
genetics- a branch of biology that studies the laws of inheritance of traits. Genetics should not be confused with genetic psychology, which studies the development of behavior from birth to death. Dictionary of a practical psychologist. M.: AST, Harvest. S. Yu. Golovin. 1998.… … Great psychological encyclopedia
Genetics(from the Greek “genesis” - origin) - the science of the laws of heredity and variability of organisms.
Gene(from the Greek “genos” - birth) is a section of a DNA molecule responsible for one characteristic, i.e., for the structure of a certain protein molecule.
Alternative signs - mutually exclusive, contrasting characteristics (the color of pea seeds is yellow and green).
Homologous chromosomes(from the Greek “homos” - identical) - paired chromosomes, identical in shape, size, set of genes. In a diploid cell, the set of chromosomes is always paired:
one chromosome from a pair of maternal origin, the other - paternal origin.
Locus - the region of the chromosome in which the gene is located.
Allelic genes - genes located in the same loci of homologous chromosomes. They control the development of alternative traits (dominant and recessive - yellow and green color of pea seeds).
Genotype - the totality of hereditary characteristics of an organism received from parents is a hereditary development program.
Phenotype - a set of characteristics and properties of an organism, manifested during the interaction of the genotype with the environment.
Zygote(from the Greek “zygote” - paired) - a cell formed by the fusion of two gametes (sex cells) - female (egg) and male (sperm). Contains a diploid (double) set of chromosomes.
Homozygote(from the Greek “homos” - identical and zygote) a zygote that has the same alleles of a given gene (both dominant AA or both recessive aa). A homozygous individual does not produce cleavage in its offspring.
Heterozygote(from the Greek “heteros” - another and zygote) - a zygote that has two different alleles for a given gene (Aa, Bb). A heterozygous individual in its offspring produces segregation for this trait.
Dominant trait(from the Latin "edominas" - dominant) - the predominant trait manifested in the offspring of
heterozygous individuals.
Recessive trait(from the Latin “recessus” - retreat) a trait that is inherited, but is suppressed, not appearing in heterozygous descendants obtained through crossing.
Gamete(from the Greek "gametes" - spouse) - a reproductive cell of a plant or animal organism, carrying one gene from an allelic pair. Gametes always carry genes in a “pure” form, since they are formed by meiotic cell division and contain one of a pair of homologous chromosomes.
Cytoplasmic inheritance- extranuclear heredity, which is carried out with the help of DNA molecules located in plastids and mitochondria.
Modification(from the Latin "modification" - modification) - a non-hereditary change in phenotype that occurs under the influence of environmental factors within the normal limits of the genotype reaction.
Modification variability - phenotypic variability. The response of a specific genotype to different environmental conditions.
Variation series- a series of modification variability of a trait, consisting of individual values of modifications, arranged in order of increasing or decreasing quantitative expression of the trait (leaf size, number of flowers in an ear, change in coat color).
Variation curve- a graphic expression of the variability of a trait, reflecting both the scope of variation and the frequency of occurrence of individual variants.
Reaction rate - the limit of modification variability of a trait determined by the genotype. Plastic traits have a wide reaction norm, while non-plastic ones have a narrow reaction norm.
Mutation(from Latin “mutatio” - change, change) - hereditary change in the genotype. Mutations can be: gene, chromosomal, generative (in gametes), extranuclear (cytoplasmic), etc.
Mutagenic factor - factor causing mutation. There are natural (natural) and artificial (man-made) mutagenic factors.
Monohybrid crossing - crossing of forms that differ from each other in one pair of alternative characters.
Dihybrid cross-cross forms that differ from each other in two pairs of alternative characteristics.
Analyzing crossing - crossing a test organism with another that is a recessive homozygote for a given trait, which makes it possible to establish the genotype of the test subject. Used in plant and animal breeding.
Chained inheritance- joint inheritance of genes localized on the same chromosome; genes form linkage groups.
Crossingovsr (cross) - mutual exchange of homologous regions of homologous chromosomes during their conjugation (in prophase I of meiosis I), leading to a rearrangement of the original combinations of genes.
Sex of organisms - a set of morphological and physiological characteristics that are determined at the moment of fertilization of an egg by a sperm and depend on the sex chromosomes carried by the sperm.
Sex chromosomes - chromosomes that differentiate males from females. The sex chromosomes of the female body are all the same (XX) and determine female gender. The sex chromosomes of the male body are different (XY): X defines feminine
floor, Y- male gender Since all sperm are formed by meiotic cell division, half of them carry X chromosomes, and half carry Y chromosomes. The probability of getting male and female is the same,
Population genetics - a branch of genetics that studies the genotypic composition of populations. This makes it possible to calculate the frequency of mutant genes, the probability of their occurrence in a homo- and heterozygous state, and also monitor the accumulation of harmful and beneficial mutations in populations. Mutations serve as material for natural and artificial selection. This section of genetics was founded by S. S. Chetverikov and was further developed in the works of N. P. Dubinin.
from Greek genesis - origin) - the doctrine of development; genetic - related to emergence and development, considered from a developmental point of view, evolutionary-historical (for example, genetic psychology).
Excellent definition
Incomplete definition ↓
GENETICS
usually defined as a science that studies the patterns of processes of heredity and variability in living organisms. The formal year of birth of genetics is considered to be 1900, although its foundations were actually formulated back in the 19th century. Austrian monk and scientist G. Mendel (1822-1884). It was Mendel, on the basis of his classical experiments on plant hybrids, already in 1865 who formulated the basic ideas of all classical genetics of the 20th century: the materiality and discreteness of heredity (the existence of special units, factors of heredity) and the random combinatorial mechanism of their transmission through generations of living organisms. Due to the central role of genetic structures in the implementation of almost all the most important processes of life, genetics in the 20th century. took a special - pivotal - place in the entire system of biological knowledge about living nature, including humans as its part. Beginning in 1900 with the rediscovery of Mendel's laws, genetics in the 20th century. has passed a rapid development path from the formal identification of genes (as the Mendelian “factors” of heredity were called at the beginning of the century) with certain sections of nuclear chromosomes to the elucidation of their true chemical nature (1944) in the form of a special class of chemical biopolymers - deoxyribonucleic acids (DNA); from the discovery of the structure of DNA in the form of the now famous and well-known double helix (1953) to deciphering the code of hereditary information (1961); and from the discovery of methods for quickly reading, determining (or, as scientists say, sequencing) long nucleotide sequences of DNA (1977) to deciphering (more precisely, sequencing) the human genome (2000).
According to recent research, there are between 24,000 and 25,000 genes in the human body. Genes are inherited from biological parents and determine things like skin color, the presence of freckles and how quickly you tan. Each gene in your body is a segment of DNA and sends signals to cells.
Scientists, doctors and nutritionists unanimously claim that genes play an important role in the susceptibility of the skin to various diseases. We constantly hear stories about people with “good” genes who can drink gallons of chocolate milk and still enjoy beautiful skin. In the past, I cursed my “bad” genes every time my skin broke out in a red rash. Genes are important and, without a doubt, they influence the condition of the skin. But is it worth seeing the reason only in them?
Researchers around the world have noticed that our genetically determined biology is unable to keep up with the dramatic changes in nutrition that have occurred in the West in recent times. What does this mean for your health? Let's think about the diet of our ancestors. It is obvious that they spent most of their time searching for food and arranging shelter. No one had any idea about processed foods and carbonated drinks, and artificial colors and flavors did not exist at all. The diet of our ancestors depended on the region of residence, but scientists were able to identify the main characteristics of their diet. They snacked on nuts, seeds, fruits, vegetables, hunted game, fished, and did not have chocolate chip cookies in their diet. Of course, your ancestors' diet may have been different from this, especially if they were Eskimos. Ancient Eskimos ate seafood and fish, so they consumed more fat and omega-3 fatty acids. Grains were not an integral part of their diet.
Whatever your ancestors, in the modern world you don't need to collect nuts and catch wild boars. Today you just go to the store and choose everything you need.
Nutrition of modern man:
processed meats such as ham, salami and sausages
dairy products (full and skim milk, cheese and butter)
white bread, flour products, cakes, cookies, refined sugar and syrups
refined oils and margarine
coffee, tea, alcoholic drinks
fruits, vegetables, fish, nuts, grains and legumes
Typically, the more processed foods a person eats, the less fruits and vegetables they end up consuming. Admit it, convenience foods are the most convenient option for dinner at the end of the workday when you are too tired to cook. Convenience is an important part of modern society, but often such nutrition has a negative impact on the condition of the skin.
In the American Journal of Clinical Nutrition, Lauren Cordain and her colleagues opined that changes in the human diet began ten thousand years ago with the advent of agriculture and animal husbandry, but more recent changes have occurred due to the consumption of too much processed food and processed foods. quite recently, so that human genetics could adapt to them. It's possible that many of us aren't victims of bad genetics at all, we're just confusing our poor genes by eating foods our bodies can't recognize.
Many scientists suggest that slow genetic adaptation to modern diets may be responsible for cancer, heart disease and acne. Research has shown that acne is very rare or non-existent in traditional cultures where people eat unprocessed foods.
With the advent of food processing, seven key changes in the human diet emerged:
1. Glycemic load has increased. Processed foods have a higher glycemic index, which raises blood glucose levels. This can damage blood vessels and lead to the development of type II diabetes.
2. The ratio of fatty acids has changed. Animals raised in artificial conditions do not receive enough exercise, so their meat contains virtually no omega-3 fatty acids, but it contains a large amount of saturated fat.
3. The proportions of proteins, fats and carbohydrates have changed. People began to consume more saturated fats and refined carbohydrates.
4. The amount of micronutrients has decreased. Processed foods like white bread and wheat flour have virtually no vitamins or minerals.
5. The acid-base balance has changed. A diet that has become habitual can cause metabolic acidosis (a shift in the body’s acid-base balance towards increased acidity), which will only increase with age. Too much acid in the body is detrimental to health.
6. The sodium-potassium balance has changed. High salt content in foods and not consuming enough fruits and vegetables means that most of us are potassium deficient. Researchers found that people began to consume 400% more salt, but significantly less vegetables and fruits.
7. Fiber content has decreased. Refined sugars and oils, alcoholic beverages and dairy products do not contain fiber. The less nutrients there are in flour products, the whiter they look.
Currently, only a small number of primitive cultures continue to eat natural foods without consuming fast food, white flour and sugar. It is incredibly interesting to study such cultures, as they demonstrate by their example the dependence of skin health on nutrition.
In today's society, where people consume white flour, dairy products and sugar, more than 79% of teenagers suffer from acne.
Surprisingly, more than 40% of men and women over 25 living in Western countries have acne.
Eskimos whose diet consists of natural products do not suffer from acne, but Eskimos whose diet is close to Western ones suffer from this disease in the same way.
Residents of the Japanese island of Okinawa eat natural foods and do not suffer from acne.
About genes
You may have a genetic predisposition to eczema, psoriasis, dark circles and cellulite, but that doesn't mean you have to suffer from them for the rest of your life. A healthy diet and a healthy daily lifestyle have an impact on genes. It turns out that a balanced diet can “turn off” problematic genes. The psoriasis gene may stop being active and simply begin to remain dormant after undergoing a program against this disease.
If you suffer from acne, cellulite, dandruff, eczema/dermatitis, psoriasis or rosacea, you will be pleased to know that this book has special programs to help you get rid of these problems (see Part III). If your baby has a skin condition that you want to treat, turn to Chapter 16. For information on how to treat seborrheic dermatitis in newborns, see Chapter 14. Alternatively, you can immediately turn to Part III, Specialized Programs ”, before you begin to study the chapters of Part II, “Eight Rules for Healthy Skin.”
If you suffer from another skin disease or have no obvious problems (and you just want to prevent premature aging), then Part II - “Eight Rules for Healthy Skin” - is suitable for you. There you will find basic recommendations that you should follow to become the owner of beautiful skin.
WARNING
Don't self-diagnose! There are many skin diseases, including serious ones, requiring constant medical supervision.
If you have not yet consulted a doctor about your skin condition, do so before starting the Healthy Skin Diet. Make sure the recommendations are right for you.
The history of the development of genetics began with the theory of evolution, which was published in 1859 by the English naturalist and traveler Charles Darwin in his book “The Origin of Species.”
In 1831, Darwin joined a five-year scientific expedition to study fossils found in rocks indicating animals that lived millions of years ago. Darwin also noted that the Galapagos Islands supported their own species of finches, which were closely related but had subtle differences that seemed to be adapted to suit their individual environments.
Upon returning to England, Darwin over the next 20 years proposed the theory of evolution occurring through the process of natural selection. The Origin of Species was the culmination of these efforts, where he argued that living things are best suited to their environment and have a better chance of surviving, reproducing, and passing on their characteristics to their descendants. This led to the theory that species gradually changed over time. His research contains some truths, such as the connection between animal and human evolution.
The book that launched the history of genetics was extremely controversial at the time, as it challenged the dominant view of the period when many people literally thought that God created the world in seven days. He also suggested that humans were animals and may have evolved from apes. He noted that after thousands of years of evolution, animals have their bodies adapted to life. If humans evolved from animals over millions of years, certain innate qualities remain today.
1859 - Charles Darwin publishes On the Origin of Species
The science of studying hereditary variability has led to the development of molecular biology for a deeper understanding of the mechanisms of hereditary variability and the science of genetics.
The initial stage of development of molecular biology
The initial development of molecular biology belongs to the Swiss physiological chemist Friedrich Miescher, who in 1869 first identified what he called the “nucleic” nuclei of human white blood cells, which we know today as deoxyribonucleic acid (DNA).
Friedrich Miescher initially isolated and characterized the protein components of white blood cells. To do this, he obtained pus-laden bandages from a local surgical clinic, which he planned to wash before filtering the white blood cells and separating their various proteins.
However, in the process of work I came across a substance that has unusual chemical properties, unlike proteins, with a very high phosphorus content and resistance to protein digestion. Miescher quickly realized that he had discovered a new substance and felt the importance of his discovery. Despite this, it took more than 50 years for the general scientific community to appreciate his work.
1869 Friedrich Miescher isolates "nucleic" acids or DNA
The DNA macromolecule ensures the storage, transmission from generation to generation and implementation of genetic information
The main initial stages of genetic development
The main stages in the development of genetics began with the teaching of the synthesis of Darwinism and the mechanisms of evolution of living things.
In 1866, the unknown monk Austrian biologist and botanist Gregor Mendel was the first person to shed light on the way in which traits are passed on from generation to generation.
Gregor Mendel is today considered the father of genetics
He was not as well known during his life, and his discoveries were largely not accepted in the scientific community. In fact, he was so ahead of the curve that it took three decades for his discoveries to be taken seriously.
Between 1856 and 1863, Mendel conducted experiments on pea plants, attempting to crossbreed and determine the “true” line in a particular combination. He identified seven characteristics: plant height, pod shape and color, seed shape, flower color and position, and coloration.
He discovered that when yellow pea and green pea plants were grown together, their offspring were always yellow. However, in the next generation of plants, the green peas returned at a 3:1 ratio.
Mendel coined the terms recessive and dominant in relation to personality traits to explain this phenomenon. So, in the example, the green trait was recessive, and the yellow trait was dominant.
1866 - Gregor Mendel discovers the basic principles of genetics
In 1900, 16 years after his death, Gregor Mendel's research into the hereditary traits of peas was finally accepted by the wider scientific community.
The Dutch botanist and geneticist Hugo de Vries, the German botanist and geneticist Carl Erich Correns, and the Austrian Erich Tsermak-Zeysenegg all independently rediscovered Mendel's work and presented results from hybridization experiments with similar conclusions.
In Britain, biologist William Bateson became the leading theorist of Mendel's teachings and an enthusiastic group of followers gathered around him. The history of the development of genetics required three decades to sufficiently understand Mendel's theory and find its place in evolutionary theory and introduce the term: genetics as a science that studies hereditary variability.
Ethical problems in the development of medical genetics
Ethical problems in the development of medical genetics have emerged since the early 1900s, when the science of eugenics (from the Greek - “good race”) was born. The meaning of the science of eugenics is to influence the reproductive qualities of certain dominant races of people. The science of eugenics is a particularly dark chapter, reflecting a lack of understanding of the relatively new discovery at the time. The term "eugenics" was first used around 1883 to refer to the "science" of heredity and upbringing.
In 1900, Mendel's theories were rediscovered, which found a regular statistical pattern for characterizing a person's height and color. In the frenzy of research that followed, one thought branched into the social theory of eugenics science. It was a huge popular movement in the first quarter of the 20th century and was presented as a mathematical science that could predict the character traits and characteristics of a human being.
Ethical issues in the development of medical genetics arose when researchers became interested in controlling the reproduction of human beings so that only those with the best genes could reproduce and improve the species. This is now used as a kind of "scientific" racism to convince people that some racial species were superior to others in terms of purity, intelligence, etc. This shows the dangers that come with practicing the science of eugenics without true respect for humanity in in general.
Many people could see that the discipline was riddled with inaccuracies, assumptions and contradictions, as well as promoting discrimination and racial hatred. However, the movement gained political support in 1924 when the Immigration Act was passed by majorities in the US House of Representatives and Senate. The law imposed strict quotas on immigration from countries of "inferior" races such as Southern Europe and Asia. When political gain and the convenient science of eugenics joined forces, ethical problems arose in the development of medical genetics.
With continued scientific research and the introduction of behaviorism in 1913, the popularity of eugenics finally began to decline. The horrors of institutional eugenics in Nazi Germany that emerged during World War II completely destroyed what was left of the movement.
Thus, from the end of the 19th to the beginning of the 20th century, the history of the development of genetics received the basic patterns of transmission of hereditary characteristics in plant and animal organisms, which were later applied to humans.
Now a science has emerged that studies the aging process of the body.
