○ Cross-crossing (reciprocal cross) : Crossbreeding between mothers with paternal genotypes and with maternal genotypes. Can know if it is sex-related

○ p generation, F1 generation (hybrid first generation), F2 generation (hybrid second generation)

⑵ Mendel’s law

① Mendel Traits : Traits whose genetic methods can be easily identified, such as Mendel’s experiment

② Plant hybrid research (1860s) : 7 Allele Genetic Study of Pea with Clear and Recessive Peas

○ Shell of beans : Round gray, wrinkled white

○ allele is an enzyme encoding starch branch enzyme (SBE) associated with amylopectin

○ Wrinkled peas have greater osmotic pressure : Wrinkles when dried in swollen state with water

○ Color of beans : Yellow, green

○ Color of flowers : White, purple (red)

○ Shape of pods : Smooth Pods, Creased Pods

○ Color of pods : Yellow, green

○ Flower blooming : Between branches

○ Stem size : Big, small

③ Peas Advantage

○ Peas have a short generation (3 months)

○ Pea leaves a lot of offspring

○ Pea is easy to grow and easy to control reproduction

○ Peas are capable of both self-fertilization and cross-fertilization.

○ Pea traits and superiority are very clear

○ A pair of alleles are far apart and follow associations but look like the law of independence

④ Design of experiments, highlighting the importance of mathematical thinking (statistics) of results

○ Mendel conducts testcross to determine if an individual is true-breeding

⑤ Mendel’s law : Law of Separation (uniform), Superiority (uniform), Independence law (positive)

○ Several types of allele are used to determine traits

○ Rule of superiority : The law states that only one parental trait appears at F1 when crossing two alleles that are alleles.

○ In other words, heterozygous means that only one allele is expressed.

○ The traits present in the heterozygote are dominant, otherwise the traits are recessive

○ Contrast with mixed theory

○ The law of separation : Because germ cells are half genes, only one of the two alleles is delivered

○ One entity inherits only two alleles from each parent

○ Forked line can be applied

○ Law of independence : Two genes that are not allele are assumed to be unigenic independently. Do not consider association

○ A_B_ : aaB_ : A_bb : aabb = 9 : 3 : 3 : Independent if 1

⑶ Genotyping via funnet squares

Example : Round yellow and wrinkle green

Figure. 2. How to draw a funnet square in Mendel pea experiment

⑷ Pedigree Analysis

Figure. 3. Family tree example

⑸ Hereditary diseases

① Cartilage development

3. Association and Cross

⑴ Drosophila Research

① Theoretical formulation of the association is made by studying fruit flies, starting with Morgan.

② Benefits of Drosophila as a Genetic Study

○ Readily available.

○ Breeding is easy and does not harm person.

○ Breeds a lot and breeds every 2 weeks.

○ 4 pairs of chromosomes.

⑵ Linkage

① Two or more non-alleles exist on the same chromosome and behave identically

② Man has 23 related groups

③ Merchant and Class

○ Merchant (coupling, cis-configuration) : Individuals with AB and ab chromosomes

○ Repulsion (trans-configuration) : Individuals with Ab and aB Chromosomes

○ When doing cross experiments, you should first determine whether you are based on merchants or traders.

④ Completely incomplete

○ Complete linkage : Association that produces only parent type. If two genes are very close and have fewer offspring

○ That is, if it is 100%

○ A_B_ : aaB_ : A_bb : aabb = 3 : 0 : 0 : 1 means merchant

○ A_B_ : aaB_ : A_bb : aabb = 2 : 1 : 1 : If 0, upper half is completely associated

○ Incomplete linkage : Produces both parental and recombinant (crossover)

⑶ Crossover

① Sister chromosome fragments exchanged during chromosome tetrad formation

○ First-division segregation (FDS) : No intersection

○ Second-division segregation (SDS) : If there is an intersection

○ chiasma (chiasma) : Where the intersection took place. Number is proportional to chromosome length

② Crossover rate is proportional to distance between two associated genes

③ Formula 1 : Crossover rate = number of germ cells at which crossover occurs ÷ total number of germ cells produced by F1 × 100

④ Formula 2 : Crossover ratio = Number of individuals resulting from intersection ÷ Number of individuals obtained as a result of the test cross × 100

⑤ Multiple crosses : The probability of multiple crosses is theoretically equal to the product of each independent single cross probability

⑥ Crossover rate up to 50% : If the distance between two genes is very distant, the law of independence is satisfied and the crossover rate at independence is 50%.

⑦ Cross rate calculation problem

○ Even crossings between two associated genes are not reflected in the crossing rate

○ Interference : Intersection of one site interferes (negative, mostly) or facilitates (positive)

○ As the distance between two genes increases, the crossover rate becomes inaccurate

⑷ Gene map

① A plot of the location of genes on a chromosome based on crossover rates obtained by three-point test crosses

○ Black cross : Crossbreeding between individuals with heterozygous genes and recessive isozytes

○ 1^st. Group two of eight objects

○ 2^nd. Multiple pairs of parents

○ 3^rd. Genes with at least one pair of individuals in between (because double-crossing is very unlikely)

○ 4^th. Calculate the crossover rate between an intermediate gene and each of the other genes

○ See. The crossover rate between the two furthest genes is less than the sum of the intermediate genes and their distance (∵ double crossover)

② 1 cM (centi-Mogan) : Lead distance with 1% crossing rate

③ At values below 25 cM, there is almost a proportional relationship between recombination frequency and guidance distance, but above that, the crossover rate is lower than that of guidance distance (e.g. double crossing).

4. Vimendel Genetics

⑴ Co-dominance : Both alleles are phenotypes

① MN blood type

② ABO blood type : IA and IB are co-dominant. i is recessive

Figure. 4. ABO blood group genetic

○ Gene encoding the glycoprotein on the surface of red blood cells on chromosome 19

○ AB type : I_AI_B

○ A type : I_AI_A or I_Ai

○ Type B : I_BI_B or I_Bi

○ O type : ii

⑵ Incomplete dominance (medium genetic) = complete phenotype only in isozygotes. Phenotype of heterozygotes is medium

① Quantitative inheritance : Usually pigments, receptors (eg : Inheritance of hypercholesterolemia and LDL receptors)

② Flower color of snapdragon : Rr × Rr → RR : Rr : rr = red : White : Pink = 1 : 2 : 1

③ Tip : The inheritance of color is not a common dominant but an incomplete dominant.

⑶ Abdominal allele : 3 or more alleles in one locus. Mainly from mutation

① Genes of the ABO blood group are determined by three alleles

⑷ Multifaceted expression : The effect of one allele is two or more phenotypes

① Cystic fibrosis : Recessive genetic disease

○ 1^st. CFTR gene defect on chromosome 7

○ 2^nd. Mutations occur in channels that transport chlorine ions out of epithelial cells

○ 3^rd. Excessive chlorine ions release much moisture out of epithelial cells

○ Symptom : Accumulation of thick mucus, repeated lung infections, digestive problems, impaired liver function, shortened lifespan

② Hemophilia : Excessive bleeding, bruising, joint pain and swelling, loss of vision, etc.

③ Sickle cell anemia : Rheumatoid arthritis, arteriosclerosis, dementia, weakened immunity, stroke, weakened heart

○ A disease in which the sixth amino acid of the β chain of hemoglobin is changed from glutamic acid (Glu, hydrophilic) to valine (Val, hydrophobic)

○ N-terminal-Val-His-Leu-Thr-Pro-Glu / Val-Glu-…

○ Hydrophilic Amino Acids Are Changed to Hydrophobic Amino Acids

○ Dominant isozygotes : Normal red blood cells

○ Recessive isozygotes : Sickle-shaped red blood cells, malaria resistance ↑↑, oxygen transfer efficiency ↓↓

○ Zygote : Only sickle-shaped red blood cells, malaria resistance ↑, oxygen transfer efficiency ↓

④ Tay-Sachs disease : Autosomal recessive

○ lipid metabolism disease caused by hexoseaminidase A deficiency

○ Manifested in newborns and died around 3 years of age

⑤ Phenylketonuria (PKU) : Autosomal diseases

○ Disease that fails to synthesize phenyl alanin hydrogenase, which hydrates phenylalanine and converts it to tyrosine

○ Tyrosine : Thyroxine production, epinephrine norepinephrine production, melanin production

○ Phenylalanine : Black urine production, phenylpyruvic acid turns into neurodevelopmental disorders → mental weakness, pale skin

○ Treatable through diet since fetal condition

⑸ Multifactorial Freedom : Quantitative inheritance involving more than one gene (seat) in one phenotype

① Distinguished from abdominal alleles in terms of one phenotype

② Skin color, eye color : Multiple melanin transpeptidase + carrier protein → melanin content

○ Melanin is a dark brown pigment made from tyrosine

○ Albinism in the absence of tyrosinase

③ At least three genes determine height

○ F1 with AABBCC × aabbcc : Normal distribution is observed when AaBbCc crosses

○ Normal distribution : ₆C₀ : ₆C₁ : ₆C₂ : ₆C₃ : ₆C₄ : ₆C₅ : ₆C₆

④ cis AB type

○ Mutations in which A and B genes exist at different loci on one chromosome

○ O children can be born from AB parents

⑹ Difference : When one gene affects the phenotype of another gene

① Fur color 9 : 3 : 4

○ Pigment gene and pigment precipitation gene are involved

○ 9 : 3 : 3 : Pigment precipitation genes from 1 reflect recessive homozygotes 3 and 1 as 4

○ Tip. 12 in any experiment : 3 : 1, 9 : 6 : 1, 9 : 3 : 4, 9 : If 7 is observed, the top!

② Bogye Gene : Non-alleles that complement one another to express one trait

③ Bombay O phenotype

○ H gene : A gene that attaches a fucose sugar to the surface of red blood cells to determine blood types

○ Type O children may be born in combinations where type O children cannot be born if the H gene is recessive homozygous. That is, the H locus is higher than the I locus

○ H gene is on chromosome 19

○ ABO allele is present on chromosome 9

④ Double recessive gene 15 : 1

⑺ Zealous death : Symptoms often develop at a young age

① AB × AB = AA, AB, BA, BB BB dies and only AA, AB, BA appear

○ A trait if A is dominant than B : B trait = 1 : Appears as a percentage of 0

○ If A is recessive than B, A trait : B trait = 1 : Appears as a ratio of 2

② Example : Cystic fibrosis, sickle cell anemia, albinoosis, Tay-Sachs disease, etc.

⑻ Dominant : Symptoms often develop late

① Genotypes and Traits. ⑺-①)

② Example : Huntingtons’ disease

○ It occurs at 30-40 years old, so it can be transmitted later

○ Progressive refractory to lethal neuronal cell death, brain dysfunction, central nervous system disorder, chorea symptoms

○ Died 10-20 years after onset of a physiological disorder

○ HD gene on chromosome 4 : 3114 aa protein code → accumulates in brain nuclei, forms toxic protein masses, and kills brain cells

○ 5’-CAG repeat sequence : Promote the Departure of RNA Polymerase

○ 5’-CAG 9-36 reps : Normal

○ 5’-CAG repeats 37-66 times : poly Q is a glutamine code, affecting 40 at 40 repetitions

○ 5’-CAG 33-36 reps : Preliminary Mutations, Likely to Increase in Offspring

○ 5’-CAG over 100 repetitions : Onset at 2 years old

③ Incomplete dominance : If the dyzygotes do not lead to fatality but have fatal symptoms such as malformations

○ Example : Cartilage development achondroplasia (achondroplasia)

⑼ Genome stamping and non-nuclear inheritance

① Dielectric Imprinting

○ Phenotypes change depending on which trait is passed from parents

○ Caused by DNA methylation (C base) (mostly due to methylation of CpG islands)

○ During germ cell generation, all genes are demethylated to release imprinting and remethylated depending on whether they are sperm or ovum

○ Male individuals receiving maternal imprints and heterozygous and recessive traits may show dominant traits due to paternal imprints

○ Example : IgF-1 Gene in Mice

○ Example 1. IgF-1 Gene in Mice : Incidental imprinting insulator methylation → transcription promotion, maternal imprinting promoter methylation → transcription inhibition

○ Example 2. Prader-Willi Syndrome and Angelman Syndrome

○ Recessive traits due to chromosomal deletion and genomic engraving

○ Prader Willi syndrome : Deleting chromosome 15. Non-deleting sites of the maternal chromosome are imprinted due to methylation, preventing the expression of the PWS gene

○ Angelman syndrome : Maternal Chromosome 15 deletion. The non-deleting site of the paternal chromosome is imprinted due to methylation, resulting in no AS gene

② Maternal effect : Cytoplasmic determinants

○ Proteins needed early in development are transferred from mothers to mRNA because they lack time to transcrib

○ Regardless of germ cell genotype, any cytoplasmic determinant is transferred to germ cells if there is any allele in the maternal line

○ Genotype and phenotype should be considered separately

○ Example : Recessive lethal genotyzygote exists when there is no problem in survival but reproduction is impossible

○ Infer the genotype of the mother from the phenotype of the offspring

○ If the children are all dominant traits, the mother’s genotype is dominant

○ If the children are all recessive traits, the mother’s genotype is recessive

○ Example : Early Drosophila, Snail Shell’s Right Helix, Left Helix, Moth Larva Eye Color Genetic

③ Cytoplasmic inheritance

○ Chromosome inheritance

○ mitochondria genetic : Maternal inheritance

○ Electron Transfer System and ATP Transpeptidase Encode mitochondria DNA

○ heteroplasmy phenomenon : Because mitochondria cooperate with many organelles (mainly the nucleus), children of mothers who are sick are not all sick.

○ Problem type 1. When following the Mendelian Gene when mating with mutants : Nuclear DNA abnormalities required for mitochondria function

○ Problem type 2. When following a maternal inheritance when mating with a mutant : mitochondria DNA abnormalities

○ Problem type 3. Leaven : mitochondria originated from parent

④ Sex-controlled inheritance : The genes are on the autosomal chromosome but the expression of the genes by sex (eg : Change of superiority)

○ Example 1. Antler gene is dominant in males. Recessive expression in females

○ Example 2. Bald genes are dominant in males encoding 5α-reductase, which converts testosterone to dehydrotestosterone (DHT) (enhancing males). Recessive expression in women

○ Women have thinning hair rather than baldness

⑤ Xenia : Paternity

⑴ Determination of sex

① Sex determination by chromosomes

○ XY type : ♂ (XY), ♀ (XO), yes : Person

○ XO type : ♂ (XO), ♀ (XX)

○ ZW type : ♂ (ZZ), ♀ (ZW), poultry

○ ZO type : ♂ (ZZ), ♀ (ZO)

○ Haploid-drainage type

② Sex determination by environment

○ Example : The reptile’s sex is determined by the incubation temperature of the eggs

③ Determination of gender by modification

○ Example : Unfertilized bees are male, fertilized bees are female

④ Gender conversion

○ Example : Some fish have only some individuals turned into males by social cues.

⑤ Hermaphrodite

○ Example : C. elegans has both male and female reproductive organs

⑵ Sex-related inheritance : Genes is sex-related, if cross-crossing results in significant differences

① 18 common genes on X and Y chromosomes

② Y chromosome-associated gene (Hansung Gene) : Very few genes. SRY genes determine sex

○ SRY (Sex Region of Y Chromosome)

○ Drosophila sex determinant is on the X chromosome

③ X chromosome-associated genetics : Males express X-associated traits more frequently than females

○ Color blindness : Green and Red Opsin Genes (X Chromosome)

○ Blue opsin gene (chromosome 7)

○ Duchenne muscular dystrophy (DMD)

○ X-chromosome recessive inheritance, incidence of 1 / 3,500 males

○ The most severe of the 10 muscular dystrophy, muscle cell degeneration

○ Adolescent dies of adulthood due to wheelchair use, breathing and heart disease

○ DMD gene : 2.4 million bp, consisting of more than 70 exons, encoding dystrophin protein

○ Dystrophin : Linkage protein between cytoskeleton and six proteins that regulate calcium ionophore in muscle cell membranes

○ DMD gene is channel deregulated due to deletion of exon

○ Hemophilia

④ Sex-controlled inheritance (See. 4-⑼) : Actually not sex-related

⑤ X inactivation : Observed only in mammals

○ Defition : Females have two X chromosomes, so inactivating one of them for quantitative compensation

○ Drosophila and pretty little nematodes double the expression of male X chromosomes for quantitative compensation

○ Barr body : Inactivated X chromosome, cause of mosaic pattern (eg : Cat pattern)

○ Only in mammals

○ Leon Hypothesis : Female early embryos randomly inactivate one X chromosome in each cell

○ Depending on the animal, the basoche occurs before or in the eggplant

○ Inactivation is irreversible but only inactivated during germ cell formation

○ If you have a basso once : All progeny cells produced by somatic cell division are condensed at the same site (eg : Cancer cells)

○ Mechanism

○ 1^st. Generation of Xist (X-inactive specific transcript) from Xist RNA on X chromosome with inactivation determined

○ 2^nd. X chromosome, determined to be activated, methylates Xist RNA to prevent inactivation mechanisms

○ 3^rd. RNA transcribed from the Xist binds to the corresponding X chromosome

○ 4^th. Blocking transcription of X chromosome, which caused RNA interference and determined inactivation

○ 5^th. Xist additionally attaches methyl groups to cytosine (C) and deacetylates histones to condense the chromosome → inhibit transcription

6. Quantitative Genetics-Genetics and the Environment

⑴ Quantitative traits : Height, weight, etc.) : Due to both genetic and environmental differences

① Genetic factors : Multifactor inheritance

○ Traits that have high inheritance indices are consistently expressed regardless of the environment

② Environmental factors : Environmental dependence of genes, environmental dependence of traits

○ Example : Study of identical twins grown in different environments

⑵ penetrance (penetrance) : The extent to which the expected traits of a particular genotype actually appear

① Complete penetrance : 100% trait is expressed as predicted by genotype

② Incomplete penetrance

③ Example : Dominant disease, which is a dominant disease, has 80% penetrance

⑶ expressivity (expressivity) : The severity of the phenotype expressed in an individual

⑷ Heritability (inheritance index) : Degree of contribution to variation within the genetic population

① Calculation through correlation analysis between groups

○ Example : Parents and offspring have the same degree of immunity

Figure. 5. Heritability example

② 0.2 to 0.4 : Genetic

③ 0.4 to : Very genetic

④ Heredity is based on populations, not individual differences

⑤ Genetic traits can also vary by environment

7. Genetic testing

⑴ Family Tree Analysis

① Tip 1. Superiority

○ When a sick parent has children who are not sick : Dominant oil field

○ If you have a sick child among parents who are not sick : Recessive oil field

② Tip 2. Determining if it is sex-related

○ Tip 2-1. When a sick father’s daughter is always sick : Dominant X-linked oil field

○ Tip 2-2. When the sick mother’s son is always sick : Recessive X-linked oil field

○ Y chromosome is less related to disease because of less gene

○ ① Determines the superiority of the chromosome and knows that it is not X-linked through tips 2-1 and 2-2.

③ Family tree problems are difficult to come out except above

⑵ Fetal examination

① Amniocentesis : Around 14-16 weeks of pregnancy. Biochemistry and karyotyping after fetal cell collection from amniotic fluid

② Chorion projections : Around 6-8 weeks of pregnancy. Biochemistry and karyotyping after chorionic villus collection

⑶ Genetic analysis

Input : 2015.6.29 22:24

72

Chapter 7. Heredity and Genetics

1. Genes and Chromosomes

2. Mendel Genetics

3. Association and Cross

4. Vimendel Genetics

6. Quantitative Genetics-Genetics and the Environment

7. Genetic testing

results matching ""

No results matching ""