Categorias: Todos - replication - genetics - meiosis - dna

por Nicholas Nguyen 6 anos atrás

195

Genetic Variance

The complexity of human genetic variance is significantly driven by several biological processes and external influences. During meiosis, the formation of gametes involves crossing over, random segregation, and independent assortment, all contributing to genetic diversity.

Genetic Variance

Genetic Variance in Humans

Examples

Meiosis
Eye color, Skin color, Hair color
DNA Replication Error
Sickle-Cell Anemia, Seasonal Flu Virus (new strains)
Cancer, Cystic Fibrosis, Crohn's Disease

Environmental Influence/Mutagens - outside agents that alters the genetic code.

Mutagens
Biological - altering DNA structure or replication via living organism, disrupting check and repair systems.
Virus
Bacteria
Chemical - chemicals that directly interact with DNA causing breakage or altering structure. Chemicals that can indirectly damage/alter DNA by enabling the creation of mutagenic compounds.
Metals
Deaminating Agent
Alkylating Agent
Intercalating Agent
Base Analog
Physical - radiation and particles damage or alter DNA structure or replication.
Heat
X-Ray
UV

DNA Replication Error - errors in replication can cause minor to significant changes in a genetic sequence.

Subtopic
Subsitution - replacing a codon or sequence with the same number of codons within a DNA strand.
Deletion - losing or "deleting" a codon or sequence from a DNA strand.
Insertion - adding or "inserting" a codon or sequence to a DNA strand.

Meiosis - the process to create gametes (egg and sperm cells) that have 1/2 the number of chromosomes as regular cells.

Crossing Over
Independent Assortment - alleles/genetic traits are inherited independently of each other (higher chance of variation).
Random Segregation - the random division of chromosomes into 4 separate gametes.
Crossing Over - the formation of recombinant chromosomes during prophase I, allowing exchange of genetic material between homologous chromosome pairs resulting in non-identical sister chromatids.