Genetic mutations presentation. Presentation on the topic: “Causes of mutations. Somatic and generative mutations. Examples of mutational variability

“Genetic diseases” - Indications for amniocentesis. Classification of gene diseases. Hereditary diseases. Genealogical method. Gene mutations. X-linked recessive type of inheritance. Autosomal recessive type of inheritance. Marfan syndrome. Impaired hemoglobin synthesis. Classification of hereditary diseases. Galactosemia.

“Inherited genetic diseases” - “Cry of the cat” syndrome. Polyploidy. Patients with Shereshevsky-Turner syndrome. Down syndrome. Danlos syndrome. Marfan syndrome. Hereditary diseases. Neurofibromatosis. Edwards syndrome. Chromosomal diseases. Klinefelter's syndrome. Gene diseases. Maurice's syndrome. Cystic fibrosis. A delicate problem. Reproductive health protection.

“Medical genetics and the human genome” - Core. Recessive inheritance. Characteristics of the human genome. Cystic fibrosis. Monogenic hereditary diseases. Epi genetic diseases. General classification genes. Diagnosis of gene diseases. Stages of implementation of genetic information. Mutation detection methods. Genome research. Hereditary diseases.

“Mutations and hereditary diseases” - Mutations. Down's disease. Statistics. Marfan syndrome. Turner syndrome. Hereditary human diseases. Cleft lip and palate. Practical genetics. Progeria. Klinefelter's syndrome. Phenylketonuria. Story. Meaning for an individual. Hemophilia. Albinism. Knowledge about types of mutations. Types of mutations.

“Examples of human chromosomal diseases” - Symptoms of Cry Cat Disease. Give a definition. Chromosome structure. Syndrome of polysomy on the Y chromosome. Inversion and ring chromosome. Triplo syndrome. Cry cat syndrome. Sex chromosome polysomy syndrome. Karyotype for Down syndrome. Human chromosomal diseases. Klinefelter's syndrome. Symptoms of the disease.

"Alzheimer's disease" - Diagnosis. Nootropics. Pathogenesis. Risk factors. Relevance. ICD-10 classification. Neurophysiological research. Clinical manifestations. Neuropsychological research. Intravital imaging brain structures. Biochemical research. Replacement therapy. Prevalence. Etiology.

There are 30 presentations in total

Akimzhan Sumbat Bt 15-21

Slide 2

Slide 3: Definitions:

Mutation Mutagens Mutation (from Latin mutatio - change, change) is any change in the DNA sequence. Mutation is a qualitative and quantitative change in the DNA of organisms, leading to changes in the genotype. The term was introduced by Hugo de Vries in 1901. Based on his research, he created a mutation theory. Mutagens are environmental factors, causing appearances mutations in organisms

Slide 4: Mutations (according to the degree of change in the genotype)

Gene (point) Chromosomal Genomic

Slide 5: Gene mutations:

A change in one or more nucleotides within a gene.

Slide 6: Sickle cell anemia -

hereditary disease associated with a disorder in the structure of the hemoglobin protein. Red blood cells under a microscope have a characteristic crescent shape (sickle shape) Patients with sickle cell anemia have an increased (though not absolute) innate resistance to malaria infection.

Slide 7: Examples of gene mutations

Hemophilia - (incoagulability of blood) is one of the most severe genetic diseases caused by a congenital lack of coagulation factors in the blood. Queen Victoria is considered the ancestor.

Slide 8: ALBINISM - lack of pigment

The cause of depigmentation is complete or partial blockade tyrosinase is an enzyme necessary for the synthesis of melanin, a substance on which the color of tissues depends.

Slide 9: Chromosomal mutations

Changes in the shape and size of chromosomes.

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Slide 10: Chromosomal mutations

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Slide 11

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Slide 12: Genomic mutations -

Change in the number of chromosomes

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Slide 13: Genomic mutations -

An “extra” chromosome in pair 21 leads to Down syndrome (the karyotype is represented by -47 chromosomes)

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Slide 14: Polyploidy

Hexoploid plant (6n) Diploid plant (2n)

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Slide 15: Human use of polyploids

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Slide 16: Mutations are distinguished:

Visible (morphological) - short legs and hairlessness in animals, gigantism, dwarfism and albinism in humans and animals. Biochemical - mutations that disrupt metabolism. For example, some types of dementia are caused by a mutation in the gene responsible for the synthesis of tyrosine.

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Slide 17

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Slide 18: There are several classifications of mutations

Mutations are distinguished according to the place of occurrence: Generative - occurring in germ cells. They appear in the next generation. Somatic - occurring in somatic cells (cells of the body) and are not inherited.

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Slide 19: Mutations by adaptive value:

Useful - increasing the vitality of individuals. Harmful - reducing the viability of individuals. Neutral - not affecting the viability of individuals. Lethal - leading to the death of an individual at the embryonic stage or after its birth

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Slide 20

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Slide 21: Mutations are distinguished:

Hidden (recessive) - mutations that do not appear in the phenotype in individuals with a heterozygous genotype (Aa). Spontaneous - spontaneous mutations are very rare in nature. Induced - mutations that occur due to a number of reasons.

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Slide 22: Mutagenic factors:

Physical factors Chemical factors Biological factors

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Slide 23: Mutagenic factors:

Physical mutagens ionizing radiation ultraviolet radiation- excessively high or low temperature. Biological mutagens some viruses (measles, rubella, influenza virus) - metabolic products (lipid oxidation products);

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Slide 24: Physical mutagens

Mutations due to the explosion in Chernobyl Scientists have found that in the 25 years after the Chernobyl disaster, genetic mutations have doubled the number congenital anomalies in descendants of people living in areas affected by radiation

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Slide 25: Chemical mutagens:

Nitrates, nitrites, pesticides, nicotine, methanol, benzopyrene. - some nutritional supplements, for example, aromatic hydrocarbons - petroleum products - organic solvents - medications, mercury preparations, immunosuppressants.

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Slide 26: Impact of chemical mutagens

Nitric oxide. A toxic substance that breaks down into nitrites and nitrates in the human body. Nitrites provoke mutations in body cells, mutate germ cells, leading to irreversible changes in newborns. Nitrosamines. Mutagens to which ciliated epithelial cells are most sensitive. Similar cells line the lungs and intestines, which explains the fact that smokers have a high incidence of lung, esophageal and intestinal cancer. Benzene. Constant inhalation of benzene contributes to the development of leukemia - cancer diseases blood. When benzene burns, soot is formed, which also contains many mutagens.

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Slide 27: Impact of chemical mutagens

Hydrogen cyanide, or hydrocyanic acid. This is a strong poison; hydrocyanic acid blocks the enzymatic activity of cells, leading to disruption of the processes of DNA division and replication. The mutations formed in this case are irreversible. Polyaromatic hydrocarbons. The most active mutagens, due to their organic origin, easily damage the genome, provoking the formation of atypical cells. The role of PAHs in the formation of squamous cell carcinoma has been proven.

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Slide 28: How to resist mutation

Eliminate from your diet foods that contain substances that are chemical mutagens. Do not expose your body to excessive infrared and ultraviolet radiation - reduce the time you spend in the sun to a minimum in the summer, protect your body from it, limit visits to the solarium Increase your immunity, reduce the incidence of viral infections Do not smoke Do not eat foods containing GMOs Do not stay in the zones radiation Do not abuse or experiment with drugs Do not pollute environment and air

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Slide 29: Mutation theory:

Mutations are rare events. These are changes in hereditary material. Mutations occur suddenly, spasmodically, without direction. Mutations are hereditary, they are passed on from generation to generation. Mutations do not form continuous series, as with modification variability. Mutations can be beneficial for the body, harmful, neutral, dominant and recessive. Mutations are individual, i.e. occur in one organism.

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Slide 30: The meaning of mutations:

Scientific research Driving force of evolution Medical direction Breeding

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Slide 31: Conclusion:

Appearing suddenly, mutations, like revolutions, destroy and create, but do not destroy the laws of nature. They themselves are subject to them.

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Last slide of the presentation: “Causes of mutations. Somatic and generative mutations"

Any deviation from the ideal case should be considered an incomparably greater value than the ordinary one, expected en masse, since along with the emergence of a negative unit stands a positive unit paving a new path. I. A. Rappoport

Slide 1

Lesson “Causes of mutations. Somatic and generative mutations"
The lesson was prepared by the biology teacher of the Astrakhan Municipal Budgetary Educational Institution “Secondary School No. 23” Medkova E.N.

Slide 2

The epigraph for the lesson can be words from the famous fairy tale by A. S. Pushkin “The Tale of Tsar Saltan”
“The queen gave birth in the night to either a son or a daughter; Not a mouse, not a frog, but an unknown animal.” A. S. Pushkin

Slide 3

Slide 4

Motivation in the lesson:
Introductory speech by the teacher about the problem of the phenomenon of mutations in humans and in the reality around them Problematic questions: Why do mutations occur? Are mutations really that dangerous? Should we be afraid of them? Can mutations be beneficial? Are mutations necessary in nature?

Slide 5

The purpose of the lesson:
deepen and expand knowledge about the molecular cytological bases of mutational variability based on the study of the main characteristics of mutational variability and the diversity of somatic and generative mutations; generate knowledge about mutagenic factors the causes of mutations based on knowledge from physics and chemistry courses

Slide 6

Lesson objectives:
Answer the questions by studying: the concept of mutation and classification of mutations, characteristics various types mutations Find out the causes of mutations in nature Summarize the lesson: The meaning of mutations in nature and in human life

Slide 7

Basic concepts:
Mutation, mutagenesis, mutagens, mutants, Mutagenic factors Somatic mutations Generative mutations
Additional Concepts
Ionizing radiation Ultraviolet radiation
Chromosomal, gene and genomic mutations Lethal mutations Semi-lethal mutations Neutral mutations Beneficial mutations

Slide 8

Definitions:
Mutation
Mutagens
Mutation (from Latin mutatio - change, change) is any change in the DNA sequence. Mutation is a qualitative and quantitative change in the DNA of organisms, leading to changes in the genotype. The term was introduced by Hugo de Vries in 1901. Based on his research, he created a mutation theory.
Mutagens are environmental factors that cause mutations in organisms

Slide 9

Mutations (according to the degree of genotype change)
Gene (spot)
Chromosomal
Genomic

Slide 10

Gene mutations:
A change in one or more nucleotides within a gene.

Slide 11

Sickle cell anemia -
a hereditary disease associated with a disorder in the structure of the hemoglobin protein. Red blood cells under a microscope have a characteristic crescent shape (sickle shape)
Patients with sickle cell anemia have an increased (though not absolute) innate resistance to malaria infection.

Slide 12

Examples of gene mutations
Hemophilia (non-clotting of blood) is one of the most severe genetic diseases caused by the congenital absence of coagulation factors in the blood. Queen Victoria is considered the ancestor.

Slide 13

ALBINISM – lack of pigment
The cause of depigmentation is the complete or partial blockade of tyrosinase, an enzyme necessary for the synthesis of melanin, a substance on which the color of tissues depends.

Slide 14

Chromosomal mutations
Changes in the shape and size of chromosomes.

Slide 15

Chromosomal mutations

Slide 16

Slide 17

Genomic mutations -
Change in the number of chromosomes

Slide 18

Genomic mutations -
An “extra” chromosome in pair 21 leads to Down syndrome (the karyotype is represented by -47 chromosomes)

Slide 19

Polyploidy
Hexoploid plant (6n)
Diploid plant (2n)

Slide 20

Human use of polyploids

Slide 21

Mutations are distinguished:
Visible (morphological) - short legs and hairlessness in animals, gigantism, dwarfism and albinism in humans and animals. Biochemical - mutations that disrupt metabolism. For example, some types of dementia are caused by a mutation in the gene responsible for the synthesis of tyrosine.

Slide 22

Slide 23

There are several classifications of mutations
Mutations are distinguished according to the place of occurrence: Generative - occurring in germ cells. They appear in the next generation. Somatic - occurring in somatic cells (cells of the body) and are not inherited.

Slide 24

Mutations by adaptive value:
Useful - increasing the vitality of individuals. Harmful - reducing the viability of individuals. Neutral - not affecting the viability of individuals. Lethal - leading to the death of an individual at the embryonic stage or after its birth

Slide 25

Slide 26

Mutations are distinguished:
Hidden (recessive) - mutations that do not appear in the phenotype in individuals with a heterozygous genotype (Aa). Spontaneous - spontaneous mutations are very rare in nature. Induced - mutations that occur due to a number of reasons.

Slide 27

Mutagenic factors:
Physical factors
Chemical factors
Biological factors

Slide 28

Questions for a conversation about physical mutagens:
1. What types of radiation do you know? 2. What radiation is called infrared? (let’s establish a connection between temperature and mutations) 3. Why is ultraviolet radiation called chemically active? 4. What is ionizing radiation? 5. What is the impact ionizing radiation on living organisms?

Slide 29

Mutagenic factors:
Physical mutagens ionizing radiation ultraviolet radiation - excessively high or low temperature. Biological mutagens some viruses (measles, rubella, influenza virus) - metabolic products (lipid oxidation products);

Slide 30

Physical mutagens
Mutations due to the Chernobyl explosion Scientists have found that in the 25 years after the Chernobyl disaster, genetic mutations doubled the number of congenital anomalies in the descendants of people living in areas affected by radiation

Slide 31

Chemical mutagens:
- nitrates, nitrites, pesticides, nicotine, methanol, benzopyrene. - some food additives, for example, aromatic hydrocarbons - petroleum products - organic solvents - drugs, mercury preparations, immunosuppressants.

Slide 32

Exposure to chemical mutagens
Nitric oxide. A toxic substance that breaks down into nitrites and nitrates in the human body. Nitrites provoke mutations in body cells and mutate germ cells, leading to irreversible changes in newborns. Nitrosamines. Mutagens to which ciliated epithelial cells are most sensitive. Similar cells line the lungs and intestines, which explains the fact that smokers have a high incidence of lung, esophageal and intestinal cancer. Benzene. Constant inhalation of benzene contributes to the development of leukemia - cancer of the blood. When benzene burns, soot is formed, which also contains many mutagens.

1. 1. © Municipal Educational Institution Oktyabrskaya Secondary School 2011 Gene mutations Performed by __10_ grade student Ekaterina Rumyantseva Biology teacher Rozina G.G.
2. 2. Definition Gene (point) mutations are changes in the number and/or sequence of nucleotides in the DNA structure (insertions, deletions, movements, substitutions of nucleotides) within individual genes, leading to a change in the quantity or quality of the corresponding protein products.
3. 3. Based on the nature of changes in the composition of a gene, the following types of mutations are distinguished: Deletions - loss of a DNA segment ranging in size from one nucleotide to a gene. Duplications - doubling or re-duplication of a DNA segment from one nucleotide to entire genes. Inversions are a 180° rotation of a DNA segment ranging in size from two nucleotides to a fragment that includes several genes. Insertions are the insertion of DNA fragments ranging in size from one nucleotide to a whole gene. Transversions are the replacement of a purine base with a pyrimidine base or vice versa in one of the codons. Transitions are the replacement of one purine base with another purine base or one pyrimidine base with another in the structure of a codon.
4. 4. classification of gene mutations by consequences Neutral mutation (silent mutation) - a mutation has no phenotypic expression (for example, as a result of degeneracy of the genetic code). Missense mutation - a replacement of a nucleotide in the coding part of a gene - leads to a replacement of an amino acid in a polypeptide. A nonsense mutation - a replacement of a nucleotide in the coding part of a gene - leads to the formation of a terminator codon (stop codon) and cessation of translation. A regulatory mutation is a mutation in the 5- or 3-untranslated regions of a gene; such a mutation disrupts gene expression. Dynamic mutations are mutations caused by an increase in the number of trinucleotide repeats in functionally significant parts of the gene. Such mutations can lead to inhibition or blockade of transcription, the acquisition of properties by protein molecules that disrupt their normal metabolism.
5. 5. Genetic diseases As of August 2001, at least 4200 monogenic diseases caused by mutations of a specific gene were listed. For a significant number of affected genes, different alleles have been identified, the number of which for some monogenic diseases reaches tens and hundreds. Depending on the functional class of the altered polypeptide (structural proteins, enzymes, receptors, transmembrane transporters, etc.), attempts are made to classify monogenic diseases according to this criterion. On currently we can say that mutant genes encoding enzymes lead to the development of enzymopathies, the most common monogenic diseases. For any monogenic disease, an essential characteristic is the type of inheritance: autosomal dominant, autosomal recessive, linked to chromosome X (dominant and recessive), holandric (linked to chromosome Y) imitochondrial.
6. 6. PolydactylyPolydactyly (from poly... and Greek dáktylos - finger), polydactyly, the presence of extra fingers on the hand or foot.
7. 7. I am a hereditary disease, which is based on a metabolic disorder in the way of converting galactose into glucose (mutation of the structural gene responsible for the synthesis of the enzyme galactose-1-phosphate uridyl transferase).
8. 8. Rickets Rickets (from the Greek ῥάχις - spine) is a disease of infants and early age, occurring with impaired bone formation and insufficient mineralization, mainly caused by a deficiency of vitamin D (see also hypovitaminosis D) and its active forms during the period of the most intensive growth of the body. The earliest characteristic changes detected by radiography in the end sections of long bones.
9. 9. Hemophilia Hemophilia is a hereditary disease associated with impaired coagulation (blood clotting process); with this disease, hemorrhages occur in the joints, muscles and internal organs, both spontaneous and as a result of injury or surgery.
10. 10. I am (from other Greek ἀ- - absence, ζῷον - animal and σπέρμα - seed) -pathological condition, in which there are no sperm in the ejaculate.
11. 11. psia psia (ancient Greek ἐπιληψία from ἐπίληπτος, “seized, caught, caught”; lat. epilepsia or caduca) is one of the most common chronic neurological diseases person, manifested in the body’s predisposition to the sudden onset of convulsive attacks
12. 12. ConclusionGene mutations cause diseases. Gene mutations that have little effect on the viability and fertility of the organism occur less frequently. This category of gene mutations, despite its relative rarity, is of great importance, since it provides the basic material for both natural selection and artificial selection, being a necessary condition for evolution and selection. Random genetic mutation.

Definition.
Classification of gene mutations.
Nomenclature of gene mutations.
The meaning of gene mutations.
Biological antimutation
mechanisms.
6. Gene properties.
1.
2.
3.
4.
5.

We continue to talk about reactions involving DNA

Replication (self-doubling of DNA)
Recombination (exchange of sites between
DNA molecules)
Reparation (self-repair of DNA)
Transcription (RNA synthesis from DNA)
Reverse transcription (DNA synthesis using
RNA - in some viruses)
Mutation (change in structure
DNA)

Warning! The lecture was difficult to understand. Please do not try to copy everything that appears on the screen, but

end
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It's better to remove it altogether.
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“Only those who do nothing make no mistakes” Popular wisdom

During replication and recombination
various
abnormalities in the DNA structure and
chromosomes that are recognized and
corrected by repair systems.
Violations in these “three R’s” can
lead to mutations.

Disturbances in one of the DNA chains –
This is not a mutation yet!
Mouton - the smallest
mutation unit –
equal to a pair
complementary
nucleotides.

Gene mutations. Definition.

Let me remind you: The structure of the eukaryotic gene.

Gene mutations – any
sequence changes
gene nucleotides
Let me remind you: The structure of the eukaryotic gene.

unique - one
copy per genome
structural - encode
protein or tRNA or rRNA
Genes
regulatory - regulate the work
structural
repetitive

Classification of mutations

Because of

Spontaneous - the reason is not clear
Induced - caused
mutagens
Mutagens are factors that cause
mutations:
physical – for example, temperature, radiation
chemical - for example, НNO2, mustard gas
biological - for example, viruses

By level

Genetic changes within one
gene
Chromosomal - structural changes
chromosomes
Genomic – changes in quantity
chromosomes
Today we are discussing
only gene mutations!

By mechanisms

Main types of gene mutations:
nucleotide substitution
insertion or deletion
nucleotides
O
180 nucleotide flip
(pairs of nucdeotides are meant everywhere)

Consequences of substitutions or insertions/deletions of one pair of nucleotides (using the example of simple text)

Nucleotide substitutions do not necessarily lead to a change in the meaning of genetic information

Missense - changes
amino acid in protein
Silent - amino acid not
is changing
Nonsense - instead of a codon for
amino acids there is a stop codon

Examples of gene mutations in humans

Missense mutation. An example is sickle cell anemia.
The replacement of a pair of nucleotides led to the replacement of an amino acid in the protein,
i.e. the primary structure changed, which entailed a change
secondary, tertiary and quaternary and forms of red blood cells.
CTT in DNA
GAA to RNA
CAT in DNA
GUA in RNA

HBB gene defect (*141900, 11p15.5). HbS is formed by the replacement of valine with glutamic acid at position 6 of the b-chain

Not for memorization!
HBB gene defect (*141900, 11p15.5). HbS is formed in
as a result of the replacement of valine with glutamic acid in
position 6 of the b-chain of the Hb molecule. In the venous bed HbS
polymerizes to form long chains,
red blood cells become sickle-shaped. It causes
increased blood viscosity, stasis; mechanical is created
obstruction in small arterioles and capillaries, which leads to
to tissue ischemia (which is associated with pain crises).

A nonsense mutation can occur either as a result of a nucleotide substitution or a reading frame shift. Example: blood type 0.

Nonsense mutation may occur
as a result of nucleotide substitution,
and when the reading frame is shifted.
Example: blood type 0.
In people with this blood type
gene loss occurred
(deletion) of one nucleotide – in
As a result, a stop codon appeared.
A short and
inactive enzyme protein.

Antigens A and B are oligosaccharides, synthesized from antigen H under the action of enzyme proteins A (allele IA) or B (allele IB).

Mutation "0" in the gene
(allele I0) led to the formation of an inactive protein.
Group 0 (H)
Group A (A)
Group B (B)
Group AB (A and B)
A
Red blood cell membrane with
different antigens
N
IN

Deletions and insertions of a large number of nucleotides are often a violation of recombination (unequal crossing over). Examples: syndrome

Large dropouts and insertions
the numbers of nucleotides are often
recombination disorder
(unequal crossing over).
Examples: Martin-Bell syndrome
(mental retardation, with
fragile X chromosome)

Mutations with the insertion of a large number of nucleotides – trinucleotide repeat expansion diseases

Fragile X syndrome (Martin-Bell syndrome). The greater the insertion of CGG repeats, the higher the degree of decline in intelligence.

FMR-1 gene
norm
premutation
complete mutation

More examples of mutations with loss of different numbers of nucleotides

Not for memorization!
Deletion of 3 nucleotides – cystic fibrosis
Deletions or insertions (insertions)
large number nucleotides – MDD and
DMD – Duchenne muscular dystrophy
(early and severe) or Becker
(late and lighter)

Cystic fibrosis is inherited in an autosomal recessive manner. The most common mutation is the loss of 3 nucleotides (triplet 508)

Not for memorization!
The secretion of secretions by the glands is disrupted

Organs affected by
cystic fibrosis (CF)
"Drumsticks" and
“watch glasses” – manifestations
chronic lung infection
Meconium ileus is a manifestation of CF

Large deletions (losses) in the dystrophin gene give rise to DMD (Duchenne muscular dystrophy), insertions (insertions) give rise to DMD (muscular dystrophy).

Becker's dystrophy).
Inherited X-linked
recessive
Not for memorization!

DMD

Let's continue the conversation about the classification of gene mutations

By localization in the gene. If a mutation occurs

in the coding part – protein synthesis
may change qualitatively
in the regulatory part - for example, in
promoter – change quantitatively
there will be nothing in the introns -
neutral (silent) mutation

By location on the chromosome

Autosomal - in autosomes
(non-sex chromosomes)
X-linked (on the X chromosome)
Y-linked (in Y)

By localization in the cell

Nuclear
Cytoplasmic (few,
but severe mitochondrial diseases)
Mitochondria have
its roundabout
DNA

Mitochondrial diseases are transmitted through the maternal line and affect muscles, vision, and the nervous system

All our cellular
organelles from moms and dads
only contribute chromosomes

By location in the body

Somatic (in body cells, most often
- cancer) are not transmitted to children
Generative (in germ cells and
will appear only in descendants)

According to the consequences

Harmful
Useful
Neutral

By manifestation in phenotype

Dominant (manifested in the phenotype
immediately both homo- and heterozygous
condition)
Recessive (appears only in
homozygous state)

Multiple allelism

The longer the gene, the more it can
be mutant alleles.
As Leo Tolstoy wrote on another occasion:
“All happy families (the norm)
happy equally. Every unhappy
the family (mutation) is unhappy in its own way.”
Thus, about 1000 gene mutations have been identified
cystic fibrosis, most rare.
The most common mutation (50% of cases) is del
508 – leads to the precipitation of phenylalanine in
position 508 of the protein and disrupts its function.

Nomenclature of gene mutations

Genes have names and places on chromosomes (“registration”), for example:

15q21.1 – fibrillin (mutation causes
Marfan syndrome)
07q31.2 – transmembrane regulator (mutation
leads to cystic fibrosis)
Xp21.2 – dystrophin (mutations - myopathy
Duchenne or Becker)
Numbering
districts is coming
from
centromere to
telomeres in
each shoulder
3
2
1
1
2
3
4
Short shoulder p
Long shoulder q

The nomenclature of genes and gene mutations is based on different approaches:

Approach 1: Genetic nomenclature (by
changes in DNA or protein)
For human genetic diseases:
Approach 2: Mendelian Inheritance in Man (OMIM)
Approach 3: Disease names

Genetic nomenclature (approach 1) is based on descriptions of changes in DNA or protein. Examples (no need to memorize!):

In DNA
3821delT - thymine deposition in
Item No. 3821.
2112ins13 kb – after nucleotide no.
2112 13,000 nucleotides were inserted
(13 kilobases)
IN PROTEIN
delF508 – loss of phenylalanine in
positions 508
N44G – replacement of asparagine with glycine
in position 44
W128X – replacement of tryptophan with stop
triplet
Alanin A Ala
Arginine R Arg
Aspartic
acid D Asp
Asparagine N Asn
Valin V Val
Histidine H His
Glycine G Gly
Glutamic
acid E Glu
Glutamine Q Gln
Isoleucine I Ile
Leucine L Leu
Lysine K Liz
Methionine M Met
Proline P Pro
Serine S Ser
Tyrosine Y Tyr
Threonine T Tre
Tryptophan W Three
Phenylalanine F Fen
Cysteine ​​C Cys
Stop triplet X

A huge role in collecting and describing gene mutations in humans belongs to Victor McKusick. He began work on compiling

mutation register.
(approach 2)
(October 21, 1921 – July 22, 2008),

(OMIM - Online Mendelian Inheritance in Man)
Each mutation gets
6 digit number
Gene mutation numbers
(OMIM)
1
100000–
199999
Autosomal dominant
2
200000–
299999
Autosomal recessive
3
300000–
399999
X-linked
4
400000–
499999
Y-linked
5
500000–
599999
600000–
Mitochondrial
6
Autosomal, described after 15
May 1994

The names of gene diseases are not systematized (approach 3)

It could just be a name
based on the manifestation of the disease -
achondroplasia – “underdevelopment of cartilage”
There may be a syndrome named after
named after a scientist (more often) – syndrome
Marfana; or sick (less often)
Can be catchy and unusual
name - Kabuki makeup syndrome,
happy doll syndrome

Achondroplasia (chondrodystrophic
dwarfism)
OMIM 100800
Mutation in the protein receptor k
growth factor
fibroblasts

Marfan syndrome
OMIM 154700
Mutation in
important protein
connecting
oh fabric –
fibrillin.
Manifestations –
high growth,
long
limbs,
stretchable
conn. textile.
How
consequence -
scoliosis,
subluxation
lens*,
aneurysm Since most mutations are harmful, nature has developed antimutational mechanisms Two strands of DNA (spare strand)
Degeneracy of the genetic code
(spare triplets)
Presence of repeating genes (spare genes)
genes)
Diploidy (spare set of chromosomes)
Repair systems (monitors at the DNA level)
The immune system(monitors the level
body)

But it’s impossible to completely avoid mutations!

harm to
individuals
benefit for
evolution

Frequency of gene mutations

Spontaneous mutations occur
spontaneously throughout life
body in normal conditions
environment.
Method for determining the frequency of spontaneous
mutations in humans is based on the appearance in
children of a dominant trait, if
he is absent from his parents.
Scientist Haldane calculated the average
the likelihood of spontaneous mutations occurring,
which turned out to be equal to 5 x 10-5 per gene
(locus) per generation.

Gene properties

Properties of a gene (not to be confused with the properties of the genetic code!)

Discreteness (has a certain size
and position - locus)
Lability (can mutate)
Stable (but rarely mutates)
Specificity (the gene encodes a specific
protein)
Allelicity (as a result of mutations
variants arise - alleles)
Pleiotropy (plurality
actions)
Dosage of action (the more
copies of the gene in the genotype (doses), those
stronger gene effect)