home Tests Define the following terms gene locus. DNA is the material basis of heredity. Structure and properties of DNA. The concepts of gene, locus, allele. Mutations. Multiple allelism. New Advances in Paternity Determination

Define the following terms gene locus. DNA is the material basis of heredity. Structure and properties of DNA. The concepts of gene, locus, allele. Mutations. Multiple allelism. New Advances in Paternity Determination

The condition of the skin indicates the functioning of internal organs and systems. The appearance of rashes of a different nature indicates the appearance of pathologies, the entry of viruses, pathogenic microorganisms, and infection into the body. Skin diseases are accompanied by itching, burning, redness, the formation of scales, peeling and dryness of the skin. If symptoms of the disease appear, you should consult a specialist. Rash and severe itching on the body in an adult, treatment, photos of formations will help to establish the cause of the appearance of rashes, prescribe a course of therapy.

Hives

Urticaria is a rash in the form of inflamed small blisters. They can affect various parts of the body, form lesions. Depending on the irritants, several forms of the disease are distinguished:

Allergic urticaria. It is characterized by high sensitivity of the body to the effects of a particular pathogen: food, chemical substances, dust, pet hair, insect bites.
Immunocomplex is distinguished by the activation of the body's production of an antigen-antibody. May occur as a result of long-term drug treatment.
An anaphylactoid reaction occurs as a result of the release of accumulated enzymes and proteins from mast cells.

The main causes of the development of the disease, rash and itching on the body in an adult are:

Photo symptoms and treatment in adults should be prescribed by a specialist, taking into account individual features patient.

Scabies

Scabies appears as a result of the action of the scabies mite on the surface of the skin. After infection, the symptoms of the photo, the first signs may appear after a few hours. The incubation period of the disease is 10-12 days.. Scabies rash quickly spreads throughout the body.

Typical symptoms of infection are:

During rash treatment and from itching on the body in an adult, as well as after undergoing a course of therapy, precautions must be taken. The body does not develop immunity to the disease, after contact with an infected surface, the rash may appear again. With scabies, it is necessary to systematically change bed linen, clothes, towels. When washing, it is necessary to disinfect things, follow the rules of personal hygiene, and systematically carry out wet cleaning.

Therapy consists of medical and external treatment.

Lichen

Lichen is characterized by the formation of nodular rashes on the skin, they are accompanied by severe itching, burning, inflammation.

Depending on the symptoms and causes of occurrence, several types of lichen are distinguished:

Sweating in adults

Prickly heat occurs in the form of small bubbles overweight people with excessive sweating. Rashes appear in those places where clothing fits snugly to the body and there is no free access of air. Also, sweating can occur when high temperature body, with dirty skin and profuse sweating.

Rashes can occur on the back, abdomen, chest, face, neck, armpits, on the folds of the arms and legs. The disease is not transmitted by direct contact. With such a rash and itching on the body in an adult no treatment required. The appearance of prickly heat may indicate dysfunctions of the endocrine, nervous, cardiovascular systems.

The main causes of prickly heat are:

increased sweating;
increase in body temperature with colds;
tight clothing made of synthetic materials;
long stay in a hot room;
overweight;
prolonged exposure to the open sun;
decorative cosmetics.

When the whole body itches, and characteristic rashes appear, measures should be taken to eliminate irritants: wear loose clothing made from natural materials, adhere to the rules of personal hygiene.

Stevens-Johnson Syndrome

Stevens-Johnson syndrome is characterized by bullous lesions of the mucous membranes and skin due to exposure to allergens. The disease can affect the mouth, eyes, and genitourinary system.

The disease can occur as a result of an infectious disease, long-term medication, malignant neoplasms. Viral, fungal, bacterial microorganisms can provoke the development of the disease: herpes, hepatitis, measles, chicken pox, tuberculosis, salmonellosis, gonorrhea, mycoplasmosis, trichophytosis, histoplasmosis.

Testify that it may be Stevens-Johnson syndrome, the following signs may:

high body temperature;
headache, malaise;
heart rhythm disturbances;
muscle pain;
sore throat, cough;
violations of the digestive tract;
large bubbles in oral cavity, which can burst, crust;
purulent inflammation of the eyeball;
the development of eye diseases such as blepharitis, keratitis;
the appearance of urethritis, vulvitis, vaginitis;

The disease can run with complications: bleeding from the bladder, pneumonia, bronchiolitis, colitis, renal failure, loss of vision.

Skin rashes appear as a sudden phenomenon on the skin in any area of the body. The rash is characterized by skin changes, redness or blanching, and itching. A symptom can form as a local reaction to external provoking factors, or it can manifest itself as a sign of the development of a pathological process. There are quite a lot of diseases that manifest themselves in the form of skin rashes, therefore the etiology of the symptom is diverse.

Etiology

Rashes on the skin in adults and in a child can be formed under the influence of such factors:

infections;
allergy;
disease of the blood and blood vessels.

Most common cause the onset of a symptom is considered an infection. Doctors refer to such diseases -, etc. These diseases manifest themselves in a characteristic rash, which is accompanied by, in the head, throat and abdomen, and a violation of the stool.

Allergic skin rashes are also often diagnosed by doctors. This form of symptom development can be recognized by the absence of signs of infection, as well as contact with the allergen. Very often, a similar reaction on the body can be noticed by the parents of the child. Provoking factors are food, animals, chemicals, drugs.

In case of violation of blood circulation and vascular disease, the patient may experience a rash for such reasons:

decrease in the number or impaired functionality of platelets;
impaired vascular permeability.

Sometimes a symptom develops in non-communicable diseases, these include:

senile keratoma;
chloasma;
flat warts;
intertrigo;

Rashes on the skin are formed with liver disease. If the organ malfunctions, the patient's skin tone changes, and a rash appears.

Characteristic red rashes can be from insect bites, acne, psoriasis, fungal diseases and scabies. Also, redness on the skin can be caused by prickly heat.

Classification

Clinicians have determined that the types of rashes can be such manifestations:

spots - there are red, brown, white maculae;
blisters - appear in a dense and rough formation on the skin;
papules - an element that looks like nodules in the thickness of the skin;
bubbles - they can be large and small, are formed in the cavity of the skin with a clear liquid;
erosion and ulcers - during the formation, the integrity of the skin is violated;
crusts - appear on the site of former blisters, pustules, ulcers.

All of these types of rashes on the body are divided into primary and secondary. The first type includes nodules, blisters, abscesses, blisters. And the second group of varieties of rash is the appearance of peeling, erosion, abrasions, crusts.

Symptoms

If skin rashes in children and adults have formed against the background of a deterioration in the functioning of the liver, then characteristic symptoms may indicate this:

If the cause was infectious diseases, then a person's skin rashes can begin on the skin of the hands, move to the face, legs, and the whole body is gradually affected. With rubella, the patient first overcomes the rash on the face and spreads throughout the skin. The first foci of inflammation are localized in places where the surface of the limbs most often bends, near the joints, on the back and buttocks. All rashes can be of different shades - pink, red, pale, brown.

Infectious pathologies often manifest themselves not only in a rash, but also in other signs. You can establish the disease in more detail according to the following clinical picture:

elevated temperature;
malaise;
pain attacks;
certain areas on the patient's body become inflamed, for example, eyes, tonsils, etc.;
may be ;
frequent heartbeat;
burning.

Rashes on the skin in the form of red spots are characteristic of the development of such infectious diseases - chickenpox, rubella, measles, scarlet fever.

Diagnostics

If any manifestations of the above symptoms are detected, the patient should urgently seek the help of a doctor. You can consult about rashes on the skin at,. After an initial physical examination and a minimal examination, the doctor refers the patient to another specialist if the cause of the disease is not inflammation, allergies, or infection.

Treatment

Treatment of allergic skin rashes is prescribed by the doctor only after the diagnosis has been made. Therapy is based on the elimination of the etiological factor, therefore, appropriate drugs must be selected.

If a person develops a rash from mechanical damage or from prickly heat, then there is nothing terrible in such a manifestation. At home, you can anoint the inflamed area with cream or oil to slightly relieve swelling and itching. Over time, the symptom will disappear. Also at home, you can eliminate the symptoms of the disease with such advice from doctors:

wear things made of natural cotton so that there is no irritation;
wash the body with baby soap or shower gel;
exclude from life all things that can cause a rash on the skin.

If the symptoms are more pronounced in the patient, have characteristic indicators, cause discomfort to the patient, then a consultation with a dermatologist is required.

If the appearance of the disease was an allergy, then it is important for the doctor to identify this allergen with the help of a sample, and then prescribe treatment. The patient must definitely move away from this item or remove the product from the diet. You can also cure such a symptom with antihistamine ointments and tablets.

If a outward sign, namely the rash, developed from the virus, and the symptoms of the disease are supplemented by fever, then the patient can be given antipyretic drugs. In case of complications of the disease, antibiotics and anti-inflammatory drugs are prescribed.

Quite often, skin rashes in diabetes mellitus, liver disease, infectious diseases or allergies are not very easy to recognize by doctors, since the symptom often manifests itself in the same indicators - itching, redness, swelling. In this regard, doctors first prescribe to the patient therapy, which is aimed at getting rid of the signs, and not the causes of the development of the disease.

Allergy is known to be a severe autoimmune disease in which the body destroys itself. It proceeds no less severely - an autoimmune disease, not contagious to others, but affecting the skin:

Rash in autoimmune diseases may appear and disappear, and then reappear and affect new areas of the skin. It is impossible to cure such a rash, they will not help. It is necessary to reprogram the body for rebirth. The cause of many autoimmune diseases lies in energy failure. As soon as a person takes a break from stress, goes to clean corners of nature, changes his diet in favor of wild berries, vegetables and fruits, natural protein, and the disease recedes.

The insidiousness of syphilis is that often the disease does not appear immediately. However, the treatment of syphilis is possible only in the early stages, when the rash is the first symptom.

A doctor, a blood test and a memo will help to recognize a dangerous disease - syphilitic rash photo in men and symptoms. Without a blood test in a dispensary, it is impossible to determine the disease. Any rash should be tested for syphilis.

In the first stage of the disease rash on the body of an adult photo with explanations in men, ulcers appear in the mouth, on the nasal mucosa, in the groin.

A chancre may appear - a seal.

It is characteristic that the sores do not hurt and soon go away on their own. Thirty days later, syphilis appears again, but already with a red-brown rash, hair loss, and ulcers.

The rash may be in the form of pink spots or papules. In this case, there are no painful sensations. Within a month or nine the secondary symptoms disappear. At the last stage of the disease, the skin can become covered with sores that do not heal, joints are deformed, internal organs and nerve cells, the brain is affected.

In the female body, syphilis manifests itself even more secretly. Apparently, this is the reason for the frequent cases of detection of diseases only at the third stage, when it is almost impossible to save the patient. A rash on a woman's body appears already in the second stage, when a lot of time has been lost for treatment. Syphilitic rash in women symptoms it is important to know in order to give yourself a chance for recovery.

Noticing rash on the body of an adult photo with explanations, spots or papules on the neck, around the mouth, arms, legs, feet and palms, you should immediately contact a dispensary to a venereologist. The rash with syphilis is different in that it is unpleasant in appearance, but does not hurt or itch. However, it may last for several months or disappear in one month. The skin looks unhealthy, so we can say that the appearance of a woman is disfigured.

In addition, the rash can be located under the mammary glands, on the inner thighs, around and inside the vagina. Eruptions on the body alternate with ulcers or appear together. Purulent sores may not disappear for a long time, but pain is not felt.

The consequences of stress and the abundance of household chemicals, harmful additives in food do not pass without a trace for a person. May suddenly appear rash on the body of an adult photo with explanations will not help, she is allergic, which indicates a malfunction in the body. The rash can be temporary or constantly worsen, taking on more and more formidable outlines. So individual papules can combine into foci.

Seeing a rash on the body, it is necessary, among other things, to visit an allergist for examination and examination, as well as to study the brochure: allergic rash on the body in an adult treatment.

The first step in allergies is to cleanse the body of toxins and allergens.

Any sorbent will do, but natural minerals are best. For example, the Litovit sorbent is able to reduce eosinophils in the blood by 90% in one month, which indicates the cleansing of the body at the intercellular level.

Dieting for food allergies essential condition successful treatment. After the tests show which foods you are allergic to, you need to eat foods that the doctor will allow.

Until the result of the samples is obtained, food provocateurs should be excluded from the diet:

Food allergies:

If you are allergic to household chemicals, you cannot wash dishes without rubber gloves. Should be washed in a washing machine. It is better to use safe plant-based products in everyday life, for example, from Amway. If you are allergic to household chemicals, the skin of the hands and face of the patient is covered with red spots, and then with a solid crust.

At the same time, the sensations are painful, and damaged skin tends to crack. Open wounds can become infected. Untreated allergies lead to psoriasis and quite often.

Red rash on the body of an adult and itches

The rash can be caused by infections or autoimmune diseases. If a rash on the body of an adult photo with explanations it itches, then such a symptom suggests that not everything is lost and measures must be taken for treatment. Worse can only be a rash that does not bother and is characteristic of syphilis.

Rash with scabies first appears on the abdomen and palms.

Outwardly, it looks like a group of small red papules filled with liquid with a dot in the center. It must be said that the dot indicates the move that the scabies mite left in the skin layer.

Comes red rash on the body of an adult and itches also with allergies, lichen planus, psoriasis.

Psoriasis rash on the body of an adult photo with explanations:

It is impossible to cure a rash, because it is necessary to treat the cause, not the effect. Such systemic diseases affect the body due to ongoing stress, medication, alcohol poisoning, or may be a complication after an infection. In all cases, the disease is preceded by a weakening of the immune system.

The absence of itching and pain during rashes in adults can be not only with sexually transmitted diseases, but also in other cases. In order not to self-medicate and diagnose on the Internet, you should visit a hospital. A rash on the body of an adult and does not itch, what can it be be explained by a dermatologist and venereologist.

If a molluscum contagiosum has invaded the body, then soon nodular formations of pink or red color will appear on the skin, similar to folds with a white liquid inside. Such nodules do not hurt and do not itch. If you press on the nodule, then the liquid contagious to humans will appear outside.

In pig breeding in Europe and America, genomic selection is beginning to be used. Its technologies make it possible to decipher the genotype of pigs already at birth and select the best animals for breeding. This latest technology is designed to further increase the breeding accuracy and reliability of the breeding value of pigs.

The ancestor of genomic selection is marker selection.

Marker selection is the use of markers for marking genes of a quantitative trait, which makes it possible to establish the presence or absence of certain genes (gene alleles) in the genome.

A gene is a section of DNA, a certain sequence of nucleotides, in which information is encoded on the synthesis of one protein molecule (or RNA), and as a result, ensures the formation of any trait and its transmission by inheritance.

Genes represented in a population in several forms - alleles - are polymorphic genes. Alleles of genes are divided into dominant and recessive. Gene polymorphism provides a variety of traits within a species.

However, only a few traits are under the control of individual genes (for example, hair color). Productivity indicators, as a rule, are quantitative traits, for the development and manifestation of which many genes are responsible. Some of these genes may have a more pronounced effect. Such genes are called quantitative trait loci (QTL) core genes. Quantitative trait loci (QTLs) are DNA segments containing genes or linked to genes that underlie a quantitative trait.

For the first time, the idea of using markers in breeding was theoretically substantiated by A.S. Serebrovsky back in the 20s. Marker, (then called "signal", English term“marker” began to be used later) according to A. S. Serebrovsky, this is an allele of a gene that has a clearly expressed phenotypic manifestation, localized next to another allele that determines an economically important trait under study, but does not have a clear phenotypic manifestation; thus, making a selection for the phenotypic manifestation of this signal allele, there is a selection of linked alleles that determine the manifestation of the studied trait.

Initially, morphological (phenotypic) traits were used as genetic markers. However, very often quantitative traits have a complex nature of inheritance, their manifestation is determined by environmental conditions and the number of markers, which are used as phenotypic traits, is limited. Then, gene products (proteins) were used as markers. But the most effective way to test genetic polymorphism is not at the level of gene products, but directly at the level of genes, that is, using polymorphic DNA nucleotide sequences as markers.

Usually, DNA fragments that lie close together on a chromosome are inherited together. This property allows the marker to be used to determine the exact inheritance pattern of a gene that has not yet been accurately located.

Thus, markers are polymorphic regions of DNA with a known position on the chromosome, but unknown functions, which can be used to identify other genes. Genetic markers must be easily identifiable, linked to a specific locus, and highly polymorphic because homozygotes provide no information.

The widespread use of DNA polymorphism variants as genetic markers began in 1980. Molecular genetic markers were used for conservation programs for the gene pools of farm animal breeds, they were used to solve the problems of the origin and distribution of breeds, establishing kinship, mapping the main loci of quantitative traits, studying the genetic causes of hereditary diseases, acceleration of selection for individual traits - resistance to certain factors, according to productive indicators. In Europe, genetic markers have been used in pig breeding since the early 1990s. to free the population from the halothane gene, which causes stress syndrome in pigs.

There are several types of molecular genetic markers. Until recently, microsatellites were very popular, since they are widely distributed in the genome and have high level polymorphism. Microsatellites - SSR (Simple Sequence Repeats) or STR (Simple Tandem Repeats) consist of DNA segments 2-6 base pairs long, repeated in tandem many times. For example, the American company Applied Biosystems has developed a test system for genotyping 11 microsatellites (TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, INRA23, ETH3, ETH225, BM1824). However, microsatellites are not enough for fine mapping of individual regions of genomes, the high cost of equipment and reagents, and the development of automated methods using SNP chips are forcing them out of practice.

A very convenient type of genetic markers is SNP (Single Nucleotide Polymorphisms) - snip or single nucleotide polymorphism- these are differences in the DNA sequence of one nucleotide in the genome of representatives of the same species or between homologous regions of the homologous chromosomes of an individual. SNPs are point mutations that can occur as a result of spontaneous mutations and the action of mutagens. A difference of even one pair of bases can cause a change in a trait. SNPs are widely distributed in the genome (humans have about 1 SNP per 1000 base pairs). The pig genome has millions of point mutations. No other type of genomic difference is able to provide such a density of markers. In addition, SNPs have a low level of mutations per generation (~10-8), in contrast to microsatellites, which makes them convenient markers for population genetic analysis. The main advantage of SNPs is the possibility of using automatic methods for their detection, for example, the use of DNA templates.

In order to increase the number of SNP markers, a number of foreign companies have recently joined forces to create a single database in order to be able to test a large number of animals tested for productivity for polymorphism to identify the presence of links between known point mutations and productivity.

Currently, a large number of polymorphic variants of genes and their mutual influence on the productive traits of pigs have been identified. Some genetic tests using performance markers are publicly available and used in breeding programs. Using such markers, you can improve some productive indicators.

Examples of productivity markers:

fertility markers: ESR, estrogen receptor gene; EPOR, erythropoietin receptor gene;
disease resistance markers – ECR F18 receptor gene;
markers of growth efficiency, meat productivity - MC4R, HMGA1, CCKAR, POU1F1.

MC4R - the melanocortin 4 receptor gene in pigs is located on chromosome 1 (SSC1) q22-q27. The replacement of one nucleotide A by G leads to a change in the amino acid composition of the MC4 receptor. As a result, there is a violation of the regulation of the secretion of adipose tissue cells, which leads to a violation of lipid metabolism and directly affects the process of formation of signs that characterize the fattening and meat qualities of pigs. The A allele determines rapid growth and large bacon thickness, and the G allele is responsible for growth efficiency and a large percentage of lean meat. Homozygous pigs with the AA genotype reach market weight three days faster than those homozygous for the G allele (GG), but pigs with the GG genotype have 8% less fat and have higher feed conversion.

Other genes that control a complex of associated physiological processes also affect meat and fattening productivity. The POU1F1 gene, a pituitary transcription factor, is a regulatory transcription factor that determines the expression of growth hormone and prolactin. In pigs, the POU1F1 locus is mapped on chromosome 13. Its polymorphism is due to a point mutation leading to the formation of two alleles, C and D. The presence of the C allele in the genotype of pigs is associated with increased average daily weight gain and greater precocity.

The markers also make it possible to test the boar genotype for sex-limited traits that appear only in sows. This, for example, is the fecundity (number of piglets per farrow), which the boar passes on to offspring. For example, testing the boar genotype for estrogen receptor (ESR) markers will allow selection of those boars for breeding that will pass on higher reproductive qualities to their daughters.

Using the results of marker selection, it is possible to estimate the frequency of occurrence of desirable and undesirable alleles for a breed or line, and further selection should be carried out so that all animals in the breed have only preferred gene alleles.

Rice. 1. The principle of operation of the oligonucleotide biochip

A DNA chip is a substrate with cells with a reagent substance deposited on it. The test material is marked with various labels (often fluorescent dyes) and applied to the biochip. As shown in the picture, the reagent substance - oligonucleotide - binds in the test material - fluorescently labeled DNA fragments - only a complementary fragment. As a result, a glow is observed on this element of the biochip.

In 2009, the pig genome was deciphered. SNP chip developed ( DNA microchip variant) containing 60,000 genetic markers of the genome. To speed up research, special robots were even created to read snips. A porcine DNA sample can be tested for the presence or absence of virtually all important point mutations that determine productive traits. Thus, the selection of the best animals can be based on genetic markers without measuring phenotypic indicators.

These advances have led to the introduction new technology- genomic selection. Genomic selection is the testing of the genome immediately after a large number genome-wide markers, so that quantitative trait loci (QTLs) are in linkage disequilibrium with at least one marker. In genomic breeding, genome scanning occurs using chips (matrices) with 50-60 thousand SNPs (which mark the main genes of quantitative traits) to identify single nucleotide polymorphisms along the animal's genome, determine genotypes with the desired manifestation of a set of productive traits, and assess the breeding value of the animal.

The term "genomic selection" was first introduced by Haley and Wisher in 1998. Meuwissen et al. in 2001 developed and presented a methodology for the analytical evaluation of breeding value using a genome-wide marker map.

The practical application of genomic selection began in 2009.

Since 2009, the largest companies in the USA (Cooperative Resources International), the Netherlands, Germany, and Australia have begun to introduce genomic selection into cattle breeding programs. Bulls of various breeds have been genotyped for over 50,000 SNPs.

Hypor First to Announce Full Market Genomic Breeding Program, which will increase the accuracy of breeding in pig breeding. It was announced in the media in June 2012 that Hypor could offer its customers Genomic Breeding Value stock.

Genetic company Hypor has been using genomic selection since 2010, working closely with the Center scientific research and new technologies of the Hendrix Genetics group (Hendrix Genetics). Hendrix Genetics tests over 60,000 SNP markers and uses this information for DNA research. The genomic index of the genetic potential of pigs is calculated after the analysis of 60,000 gene markers (snip) for the animal. In theory, if there are enough genetic markers to cover all the DNA of a pig (its genome), it is possible to describe all genetic variations for all measurable traits. Modern mathematical-genetic software for data processing is being prepared.

The genetic company Hendrix Genetics has a large biobank - it stores blood and tissue samples of breeding animals of several farms and generations for DNA research (identification of the genetic value of animals) and analysis of the animal genotype. Hypor has been conducting pig DNA testing at its breeding plants for over two years. All samples from different breeding plants located in different countries, are sent for processing to the new central Hendrix Genetics Genomics Laboratory in Ploufragant (France). Gerard Albers, Director of the Center for Research and New Technologies, emphasizes: "The Genomic Lab is a valuable asset shared by all the genetic companies that make up Hendrix Genetics and is truly unique in the swine industry."

Genomic selection is a powerful tool for future use. Currently, the effectiveness of genomic selection is limited by the different nature of the interaction between the loci of quantitative traits, the variability of quantitative traits in different breeds, and the influence of environmental factors on the manifestation of a trait. But the results of studies in many countries have confirmed that the use of statistical methods in conjunction with genomic scanning increases the reliability of breeding value prediction.

Selection of pigs using statistical methods for some indicators (for example, disease resistance, meat quality, fertility) is characterized by low efficiency. This happens due to the following factors:

low heritability of traits,
great influence on this sign of environmental factors,
due to sex-limited manifestation,
manifestation of a trait only under the influence of certain factors,
when the manifestation of the symptom occurs relatively late,
due to the fact that the characteristics are difficult to measure (for example, health characteristics),
the presence of hidden carriers-signs.

For example, such a defect in pigs as stress sensitivity is difficult to diagnose and manifests itself in increased mortality of piglets under the influence of stress (transportation, etc.) and deterioration in meat quality. DNA testing using gene markers makes it possible to identify all carriers of this defect, including latent ones, and to carry out selection taking this into account.

To assess productivity indicators that are difficult to predict by statistical methods, for a more reliable assessment of them, an analysis of the offspring is needed, that is, it is necessary to wait for the offspring and analyze its breeding value. And the use of DNA markers makes it possible to analyze the genotype immediately at birth, without waiting for the manifestation of a trait or the appearance of offspring, which significantly speeds up selection.

Index evaluation of animals is carried out according to the exterior and productive qualities (early maturity of piglets, etc.). In both cases, phenotypic indicators are used, therefore, in order to use these traits in calculations, it is necessary to know their heritability coefficient. However, even in this case, we will be dealing with the probability of the genetic substantiation of any trait, the average indicators of its ancestors and descendants (there is no way to determine which genes a young animal inherited: better or worse than this average). With the help of genotype analysis, it is possible to accurately establish the fact of inheritance of certain genes already at birth, to evaluate genotypes directly, and not through phenotypic manifestations.

However, if pigs are selected for traits that are highly heritable, such as an easily quantifiable number of teats, genomic selection will not bring significant benefits.

Marker selection does not negate traditional approaches to determining breeding value. Statistical analysis and genomic selection technologies complement each other. The use of genetic markers makes it possible to speed up the process of animal selection, and index methods - to more accurately assess the effectiveness of this selection.

Genomic breeding is an opportunity to make pig production a precision production. The use of genomic selection technologies will make it possible to produce a variety of meat products that meet consumer demand.

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gene locus- geno lokusas statusas T sritis augalininkystė apibrėžtis Geno vieta chromosomoje. atitikmenys: engl. gene locus rus. gene locus... Žemės ūkio augalų selekcijos ir sėklininkystės terminų žodynas

This term has other meanings, see Locus (meanings). Schematic representation of a chromosome: (1) Chromatid, one of two identical parts of a chromosome after S phase. (2) Centromere, the place where the chromatids are together ... Wikipedia

Locus(s)- * locus(s) * locus(es) 1. The location of a certain gene (its specific alleles) on a chromosome or within a segment of genomic DNA. 2. The location of a given mutation or gene on the genetic map. Often used instead of the terms "mutation" ... ... Genetics. encyclopedic Dictionary

Locus: Locus in biology means a fixed position (localization) on a chromosome, such as the position of a gene. Locus is a monthly American magazine, subtitled "The Science Fiction and Fantasy Magazine". Locus literary prize... Wikipedia

- (lat. locus) the location of a particular gene on the genetic map of the chromosome ... Big Encyclopedic Dictionary

- (from lat. locus place), the location of a particular gene (its alleles) on the genetic. or cytology. chromosome map. Sometimes the term "L." unjustifiably used as a synonym for the term "gene". .(Source: Biological encyclopedic Dictionary." Gl. ... ... Biological encyclopedic dictionary