2.0x Genetics
2026-02-21 22:29
Status: #new
2.x Genetics
Essentials of genetics
Mendel's experiments
Mendel's Traits
Genetic Crosses
- A test cross is done to determine the genotype of an organism.
Mendell's Law of Independent Assortment
- Each chromosome of a complete set is distributed to separate gametes independent of each other. (Each loci of Gene is located in separate locations)
- Each trait is inherited independently regardless of inheritance of the other trait
Punnet Squares
- Developed to visualize Mendel's experiments from a genetic perspective
- For every organism we use for a cross (in a hypothetical fertilization), it is necessary to define its genotype (its genetic makeup)
Dihybrid Cross
- This crosses two traits simultaneously
Monohybrid Cross
- This tests only one trait to be examined at a time
General Rule when Making Punnet Squares
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- Identify the Organism in the cross
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- Define Variables for the alleles
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- Generate gametes and complete the Punnet Square
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- Provide the phenotype%
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- Provide the genotype%
- ie.
Simple Mendelian Genetics
- Work with Dominant and Recessive Alleles
Patterns Observed
- Autosomal Dominant
- Disorder Requires at least a heterozygous gene to manifest
- Autosomal Recessive
- Disorder Requires at least a homozygous recessive gene to manifest
Genetic Applications
Genetic Testing
- There are many tests for different genetic abnormalities
- ie. CFTR (Cystic fibrosis transmembrane conductance regulator)
Genetic Counselling
- People with history of genetic abnormalities can go to genetic counselling to determine the likelihood of passing on disease alleles
Gene-therapy
- Targets a abnormal DNA allele, and swaps it with a wild type allele
- Some approve methods are in clinical trials
- Methods
- Direct deliver: The gene is put in a virus and the virus is injected in the patient.
- Cell-based delivery: Stem cells are extracted, and using the virus, the steam cells grow into cured cells which can then be reinsirted
Cloning
- A clone is a organism with the same genetics as the donor organism
- Transfer the nucleus from a somatic cell into a ova with its nucleus removed
- (Somatic Cell Nuclear Transfer)