Health by inheritance: what diseases are transmitted genetically

Health by inheritance: what diseases are transmitted genetically

I. Fundamentals of genetic heredity and health

1. Human genome: instructions for the operation of the body.

   • The human genome is a complete set of genetic information encoded in DNA (deoxyribonucleic acid). It consists of approximately 20,000-25,000 genes located in 23 pairs of chromosomes (46 chromosomes in total). One set of chromosomes (23) is inherited from the mother, and the other (23) – from the father.
   • Genes are functional units of heredity containing instructions for protein synthesis. Proteins, in turn, perform many functions in the body, including cell construction, catalysis of chemical reactions, transportation of substances and protection against infections.
   • The genome is not static. It is influenced by environmental factors, lifestyle and mutations that can occur spontaneously or under the influence of external factors (for example, radiation or chemicals). These changes can lead to various diseases, including hereditary ones.

2. Mechanisms of heredity: dominant and recessive genes.

   • Genes exist in various forms called alleles. Each person has two alleles for each gene inherited from each of the parents.
   • Dominant allele It shows its effect even in the presence of one copy. If a person has at least one dominant allele for a certain attribute, this sign will manifest.
   • Recessive allele It shows its effect only if a person has two copies of this allele (that is, he is homozygothered according to the recessive allele). If a person has only one recessive allele, he will be the bearer of this allele, but the sign will not appear.
   • Copomination – The situation is when both alleles appear simultaneously. For example, a blood type AB is an example of codomination.
   • Incomplete dominance – The situation is when the phenotype of heterozygotes (possessing one dominant and one recessive allele) is intermediate between the phenotypes of homozygots for each of the alleles.

3. Types of genetic disorders: mutations and chromosomal abnormalities.

   • Mutations – These are changes in the sequence of DNA. They can arise spontaneously or under the influence of external factors. Mutations can be neutral, useful or harmful.
   • Crack mutations: Replacing, insert or removal of one nucleotide.
     • Replacing the grounds: One nucleotide is replaced by another (for example, adenine with guanine).
     • Insert: Adding one or more nucleotides to the DNA sequence.
     • Delegation: Removal of one or more nucleotides from a DNA sequence.
   • Chromosomal abnormalities: Changes in the structure or quantity of chromosomes.
     • ANEULOIDIDID: The abnormal number of chromosomes (for example, trisomy 21 – Down syndrome).
     • Deletions: Loss of part of the chromosome.
     • Duplications: Repetition of a section of the chromosome.
     • Inversions: The section of the chromosome is turned 180 degrees.
     • Translocations: Transfer of a chromosome section to another chromosome.

4. Multifactorial diseases: the influence of genes and the environment.

   • Many common diseases, such as cardiovascular diseases, diabetes, cancer and mental disorders, are multifactorial. This means that their development is associated with the interaction between genetic factors and environmental factors (for example, diet, lifestyle, toxins).
   • The genetic predisposition increases the risk of the development of the disease, but does not guarantee its appearance. Environmental factors can both increase and reduce this risk.
   • The study of multifactorial diseases is a difficult task, since it is necessary to take into account many factors and their interaction.
   • Examples of environmental factors: diet, physical activity, smoking, alcohol use, exposure to chemicals, stress.

II. Hereditary diseases: categories and examples

1. Autosomal dominant diseases.

   • To manifest the disease, it is enough to inherit one mutant allele from one of the parents.
   • In a sick parent, the probability of transferring the mutant allele to the offspring is 50%.
   • Examples:
     • Type 1 neurofibromatosis (NF1): The disease characterized by the formation of tumors (neurofiber) on the nerves, spots of the color “coffee with milk” on the skin and other symptoms.
     • Marfan syndrome: Disease of connective tissue, affecting the heart, blood vessels, eyes and skeleton.
     • Achondroplasia: The most common form of dwarf, characterized by shortening of the limbs.
     • Polycystic kidney (autosomal dominant): The disease characterized by the formation of multiple cysts in the kidneys, which leads to renal failure.
     • Huntington disease: Neurodegenerative disease leading to progressive motor, cognitive and psychiatric disorders.

2. Autosomal recessive diseases.

   • The disease manifests itself only if a person inherited two mutant alleles, one of each of the parents.
   • Parents are carriers of the mutant allele and usually do not show signs of the disease.
   • The probability of the birth of a sick child in two carrier parents is 25%. The likelihood of the birth of a carrier child is 50%. The probability of the birth of a healthy child is 25%.
   • Examples:
     • Cykovyskidosis (cystic fibrosis): A disease that affects the lungs, pancreas and other organs, leading to the accumulation of thick mucus.
     • Phenylketonuria (FCU): A disease in which the body cannot split the phenylalanine amino acid, which leads to the accumulation of phenylalanine in the blood and damage to the brain, if you do not begin treatment in early childhood.
     • Sickle -cell anemia: Blood disease in which red blood cells have a sickle form, which leads to chronic anemia, pain and other complications.
     • Talasemia: A group of hereditary blood diseases characterized by a violation of hemoglobin synthesis.
     • Tey-Saxi disease: A serious neurodegenerative disease, which usually manifests itself in infancy and leads to death in early childhood. Ashkenazi is more common in people of Jewish origin.

3. X-linked dominant diseases.

   • The gene responsible for the disease is located on the X-chromosome.
   • Women have two X-chromosomes, therefore, one mutant X-chromosome is enough to manifest the disease.
   • Men have one X-chromosome, so if they have a mutant gene on the X-chromosome, they will certainly get sick.
   • If a sick mother (having one mutant X-chromosome) is born a daughter, the probability that the daughter will inherit the mutant X-chromosome and will be sick, is 50%. If a sick mother is born a son, the probability that the son will inherit the mutant X-chromosome and will be sick, is 50%.
   • If a sick father (having a mutant X-chromosome) gives birth to a daughter, then all daughters will inherit the mutant X-chromosome and will be sick. If a sick father gives birth to a son, then the sons do not inherit the X-chromosomes of his father and will not be sick.
   • Examples:
     • Vitamin D-resistant rickets (hypofosphatemic rickets): The disease characterized by impaired metabolism of vitamin D and phosphorus, which leads to bone deformation.
     • Retta syndrome: A neurological disease that affects mainly girls and leads to a delay in development, the loss of acquired skills and other problems.

4. X-linked recessive diseases.

   • The gene responsible for the disease is located on the X-chromosome.
   • In women with two X-chromosomes, the disease is manifested only if they have two mutant alleles on both X-chromosomes. If a woman has only one mutant allele, she is a carrier and usually does not show signs of the disease, but can convey a mutant allele to her children.
   • In men who have only one X-chromosome, the disease manifests itself if they have a mutant gene on the X-chromosome.
   • If the mother is the bearer of the mutant allele, the probability of the birth of a sick son is 50%. The probability of the birth of a ladder daughter is 50%.
   • If his father is sick, then all his daughters will be carriers of the mutant allele. All his sons will be healthy.
   • Examples:
     • Hemophilia: The disease characterized by impaired blood coagulation, which leads to bleeding.
     • Dyushenna’s muscle dystrophy: A progressive muscle disease that affects mainly boys and leads to disability and death.
     • Daltonism (color blindness): Violation of color vision.

5. Y-linked diseases.

   • The gene responsible for the disease is located on the Y chromosome.
   • The Y-chromosome is transmitted only from father to son.
   • All the sons of the sick father will be sick.
   • Daughters do not inherit the Y-chromosome and will not be sick.
   • Examples: Y-Scheduled diseases are rare. Most Y-linked genes are associated with the development of male sexual characteristics and infertility.
     • Male infertility (some forms): Violation of spermatogenesis leading to infertility.

6. Mitochondrial diseases.

   • Mitochondria is organelles inside the cells that produce energy. They have their own DNA (MTDNK).
   • Mitochondrial diseases are caused by mutations in MTDNK.
   • MTDNK is transmitted only from mother to child.
   • All children of the sick mother will inherit mutant MTDNK, but the severity of the disease can vary.
   • Fathers do not give MTDNK to their children.
   • Examples:
     • MELAS (mitochondrial encephalopathy, lactacidosis and stroke -like episodes): A disease that affects the brain, muscles and other organs, leading to neurological problems, muscle weakness and other symptoms.
     • Merrf (myoclonic epilepsy with torn red fibers): A disease that affects the brain and muscles, leading to myoclonic cramps, muscle weakness and other symptoms.
     • Leia syndrome: A severe neurodegenerative disease, which usually manifests itself in infancy or early childhood and leads to death.

7. Chromosomal abnormalities.

   • Down Syndrome (Trisomy 21): The presence of an additional 21st chromosome, leading to a delay in mental development, characteristic physical characteristics and other health problems.
   • Turner syndrome (monosomy x): The absence of one X-chromosome in women, leading to low growth, infertility and other health problems.
   • Klainfelter syndrome (XXY): The presence of an additional X-chromosome in men, leading to infertility, gynecomastia and other health problems.
   • Patau’s Syndrome (Trisomy 13): The presence of an additional 13th chromosome, leading to severe malformations and death at an early age.
   • Edwards syndrome (Trisomy 18): The presence of an additional 18th chromosome, leading to severe malformations and death at an early age.

III. Genetic predisposition to common diseases

1. Cardiovascular diseases.

   • Family hypercholesterolemia: A hereditary disease characterized by a high level of cholesterol in the blood, which increases the risk of developing cardiovascular diseases at an early age.
   • Hypertension (arterial hypertension): A genetic predisposition plays an important role in the development of hypertension. Several genes are associated with the regulation of blood pressure.
   • Corny heart (coronary heart disease): Genetic factors can affect the risk of IBS, including the formation of atherosclerotic plaques in the arteries.
   • Cardiomyopathy: The disease of the heart muscle, which can be caused by genetic mutations.

2. Diabetes.

   • Type 1 diabetes: Autoimmune disease in which the immune system attacks and destroys pancreatic cells that produce insulin. A genetic predisposition plays an important role, especially HLA genes (human leukocytic antigen).
   • Type 2 diabetes: The disease characterized by resistance to insulin and insufficient production of insulin. A genetic predisposition is an important risk factor, especially in combination with environmental factors, such as obesity and lack of physical activity.

3. Cancer.

   • Breast and ovary cancer: Mutations in the BRCA1 and BRCA2 genes significantly increase the risk of breast cancer and ovaries.
   • Colorectal cancer (colon cancer): Some hereditary syndromes, such as linch syndrome (hereditary non -fluid colorectal cancer) and family adenomatous polyposis (FAP), increase the risk of colorectal cancer.
   • Prostate cancer: A genetic predisposition plays a role in the development of prostate cancer.
   • Melanoma: Genetic factors can affect the risk of developing melanoma.

4. Mental disorders.

   • Schizophrenia: The disease characterized by hallucinations, delirium and other disorders of thinking and behavior. Genetic predisposition plays an important role.
   • Bipolar disorder: The disease characterized by mood swings from mania to depression. Genetic predisposition plays an important role.
   • Depression: Genetic factors can affect the risk of depression.
   • Autism: A genetic predisposition plays an important role in the development of autism.
   • Attention deficit syndrome (HDVG): Genetic factors can affect the risk of ADHD.

5. Neurological diseases.

   • Alzheimer’s disease: A genetic predisposition plays a role in the development of Alzheimer’s disease, especially in the early onset of the disease. The APOE4 gene is an important risk factor.
   • Parkinson’s disease: Genetic factors can affect the risk of Parkinson’s disease.
   • Epilepsy: Some forms of epilepsy are hereditary.
   • Scattered sclerosis: A genetic predisposition plays a role in the development of multiple sclerosis.

6. Autoimmune diseases.

   • Rheumatoid arthritis: A genetic predisposition plays an important role in the development of rheumatoid arthritis. HLA genes are associated with an increased risk of disease.
   • System red lupus (SLE): Genetic factors can affect the risk of developing well.
   • Crohn’s disease and ulcerative colitis (inflammatory intestinal diseases): A genetic predisposition plays an important role in the development of these diseases.
   • Celiac disease (glutenic enteropathy): Genetic predisposition is an important risk factor for the development of celiac disease.

IV. Genetic counseling and testing

1. When should be addressed to the genetics consultant?

   • Family history of hereditary diseases.
   • Repeated miscarriages or infertility.
   • The birth of a child with congenital malformations or developmental delay.
   • Suspicion of a hereditary disease in yourself or in a family member.
   • Planning pregnancy over the age of 35 years.
   • Blood kinship between partners.
   • The desire to find out the risk of transmitting a hereditary disease to offspring.
   • A positive result of genetic screening.

2. Types of genetic tests.

   • Cariotipirani: Analysis of chromosomes to identify anomalies in the amount or structure of chromosomes.
   • Fish (fluorescent in situ hybridization): The method used to identify specific DNA sequences on chromosomes.
   • PCR (polymerase chain reaction): The method used for amplification (multiplication) of specific DNA sequences.
   • DNA sequencing: Determination of the sequence of nucleotides in DNA.
   • Eczu sequencing: Sequencing of all encoding areas (exons) of genes.
   • Full -seed sequencing: Sequencing of the entire genome.
   • Preimplantation genetic diagnostics (PGD): Genetic testing of embryos obtained as a result of in vitro fertilization (IVF) before implantation into the uterus.
   • The prenatal diagnostics: Genetic testing of the fetus during pregnancy (for example, amniocentesis, choriona biopsy).
   • Newborns screening: Genetic testing of newborns to identify some hereditary diseases that can be treated at an early age.

3. Ethical and social aspects of genetic testing.

   • Confidentiality of genetic information: It is important to protect genetic information from unauthorized access and use.
   • Discrimination based on genetic information: It is necessary to avoid discrimination against people on the basis of their genetic predisposition to diseases.
   • The psychological impact of genetic testing: The results of genetic testing can have a significant psychological impact on people, so it is important to provide them with support and consultations.
   • Reproductive choice: Genetic testing can help people make informed decisions on family planning.
   • Availability of genetic testing: It is necessary to ensure equal access to genetic testing for all, regardless of their socio-economic status.

V. Prevention and treatment of hereditary diseases

1. Early diagnosis and screening.

   • Screening of newborns allows you to identify some hereditary diseases at an early age, when treatment is most effective.
   • Genetic counseling and testing can help identify people with an increased risk of developing hereditary diseases.
   • Regular medical examinations and examinations can help identify diseases in the early stages.

2. Change in lifestyle.

   • Healthy nutrition, regular physical exercises and smoking refusal can reduce the risk of developing many multifactorial diseases such as cardiovascular diseases, diabetes and cancer.
   • Avoiding the effects of toxins and harmful substances can reduce the risk of developing certain hereditary diseases.
   • Stress management can improve the general health and reduce the risk of developing certain diseases.

3. Drug treatment.

   • Many hereditary diseases can be treated with drugs.
   • In some cases, it is possible to use genetic therapy to correct mutant genes.
   • Personalized medicine based on human genetic information can help choose the most effective treatment.

4. Surgical treatment.

   • In some cases, surgical treatment may be necessary for the treatment of hereditary diseases.
   • Organ transplantation may be a treatment option for some hereditary diseases.

5. Gene therapy.

   • Gene therapy is an experimental approach to the treatment of hereditary diseases, which consists in introducing a healthy copy of the gene into the patient’s cells.
   • Gene therapy has the potential for the treatment of many hereditary diseases, but is still in the early stages of development.

6. Supporting therapy and rehabilitation.

   • Supporting therapy and rehabilitation can help people with hereditary diseases improve the quality of life and cope with the symptoms of the disease.
   • Physiotherapy, labor therapy, speech therapy and psychological support can be useful for people with hereditary diseases.

VI. Recent achievements in the field of genetics and hereditary diseases

1. The development of new generation sequencing technologies (NGS).

   • NGS allows you to quickly and cheaply seize large areas of DNA, which facilitates the detection of genetic mutations.
   • NGS is used to diagnose hereditary diseases, identify a genetic predisposition to diseases and develop personalized treatment methods.

2. Development of CRISPR-CAS9 genome editing technologies.

   • CRISPR-CAS9 is a powerful technology that allows you to accurately edit genes.
   • CRISPR-CAS9 has a potential for the treatment of hereditary diseases by correcting mutant genes.

3. The use of artificial intelligence (AI) in genetics.

   • AI is used to analyze large volumes of genetic data, identifying patterns and developing new methods of diagnosis and treatment of hereditary diseases.
   • AI can help doctors make more reasonable decisions on the treatment of patients with hereditary diseases.

4. The development of personalized medicine.

   • Personalized medicine uses human genetic information to select the most effective treatment.
   • Personalized medicine has a potential for improving the treatment of hereditary diseases.

5. New approaches to genetic therapy.

   • New approaches to gene therapy are being developed, which allow more efficiently and safely delivered genes to the patients of the patient.
   • These new approaches can make genetic therapy available for more people with hereditary diseases.

VII. Resources and support for people with hereditary diseases

1. National and international organizations.

   • National organizations specializing in specific hereditary diseases can provide information, support and resources for people with these diseases and their families.
   • International organizations engaged in genetics and hereditary diseases can provide information about the latest achievements in the field of research and treatment.

2. Online resources and forums.

   • Online resources and forums can provide people with hereditary diseases with the opportunity to communicate with other people who are faced with similar problems, share experience and receive support.

3. Support groups.

   • Support groups can provide people with hereditary diseases with the opportunity to communicate with other people who are faced with similar problems, share experience and receive full -time support.

4. Genetic consultants and geneticist doctors.

   • Genetic consultants and geneticist can provide information about hereditary diseases, genetic testing, risks and treatment capabilities.

5. Psychological support.

   • Psychological support can help people with hereditary diseases cope with emotional and psychological problems associated with the disease.

This detailed outline provides a comprehensive framework for a 100,000-word article on genetic inheritance and diseases. Expanding on each of these points with well-researched information, examples, case studies, and current research findings will create a high-quality and informative resource for readers. Remember to cite sources properly and maintain a clear and accessible writing style. Good luck!