Genetic Diversity

• DNA contains deoxyribose
• purines


  adenine and guanine
• pyrimidines


  thymine and cytosine
• RNA contains ribose
• mRNA


  messenger, intermediate between DNA and proteins
• DNA to mRNA is transcription
• transcription


  DNA to mRNA
• translation


  mRNA to proteins
• What are the protein structures?

  primary secondary tertiary quaternary
• central dogma of molecular biology 


  flow of information from transcription to translation
• mutation in genes cause defects in steps in metabolic pathways
• bacteriophage infect bacteria by injecting DNA
• specific base paring explain how genetic information is copied and transferred
• genetic code showed how DNA sequence information is translated into Aa sequences
• human genome nomenculture organisation


  approves a gene name and symbol for each known human gene
• sequence ontology constorium


  a set of terms and relationships used to describe the features and attributes of biological sequence
• genetic diversity


  heritable variation withing and between populations of organisms
• epigenetic variation


  differences in gene expression not sequence
• genetic variation


  differences in bases of DNA
• mutation is the ultimate source of genetic variation
• point mutations


  change is a single base in either deletion, substitution, insertion, inversion
• larger mutations include duplication, inversion, deletion, insertion, translocation
• silent mutation


  does not change the Aa
• mutation is random
• non-coding DNA typically changes faster than that of coding DNA
• different part of DNA evolve at different rates
• Mendel's law of independent assortment 


  two alleles for a heritable character segregate during gamete formation and end up in different gamete
• hemizygous


  XY
• character


  observable physiological feature
• trait


  form of character
• genotype


  genetic makeup of an organism
• phenotype= genotype + environment
• measuring diversity in an individual is shown in percentage of heterozygotes
• genetic diversity within a population is measured frequencies of genes at a set loci
• all homozygous have a frequency of 0-1
• all heterozygous have a frequency of 0.5
• loss of genetic diversity means a reduction in evolutionary options in the long term
• genetic bottlenecking


  populations crash to very low levels and then recover but have a reduced genetic diversity
• bottlenecking means reproductive success decreases
• small populations lose genetic diversity overtime