Genetic Methods

• What is genetic research?

  the study of how traits are passed from generation to generation
• How did Mendel do the first genetic research?

  cross bred pea plants
• What did Mendel find about genetics?

  peas get one version of each trait from each parent (allele), some seemed to be dominant while others were recessive
• What are dominant alleles?

  Dominant traits are easily expressed in an organism's phenotype
• What are recessive alleles?

  Alleles that are only expressed when paired with another recessive allele
• What are the 2 laws of Mendelian inhereitance?

  1. Segregation: Traits are either dominant or recessive, cannot be both
  2. Independence: Varieties of each trait sort independently of each other
• How are chromosomes formed?

  during DNA replication
• How many chromosomes do humans have?

  46 chromosomes (23 pairs)
• How do chromsomes determine sex?

  ll pairs are XX, aside from the final pair which may vary. This pair codes for biological sex, with biological females having XX and males having XY
• What are genes?

  Genes are segments of DNA that contain the instructions for building and maintaining an organism's cells and tissues
• What is the genome?

  The genome is the complete set of genetic material or DNA present in an organism
• What is it called when phenotype traits are programmed by a single gene?

  pleiotropic
• What is it called when phenotype traits are programmed by a multiple genes?

  polygenic
• What is the human genome project?

  A scientific research project that aimed to map and sequence the entire human genome, helps with medicine and QOL imporvement
• What 3 things dont follow Mendel's laws?

  • X-linked conditions
  • sporadic mutations
  • polygenic traits
• What are X-linked conditions?

  • Some recessive traits are more prevalently expressed in males than females as they may not have a dominant allele on their (much shorter) Y chromosome
  • e.g. colour blindness, Turner syndrome
• What are sporadic mutations?

  • Caused by errors or interference in typical cell division, often includes errors in chromosomal numbers
  • e.g. Downs Syndrome has an extra version of chromosome 21
• What are polygenic trait disorders?

  • These conditions or disorders reply on coding from multiple genes and may not consistently follow Mendelian rules, e.g. schizophrenia
  • Individuals are considered to be genetically predisposed to develop schizophrenia, suggesting a clear genetic basis but some interaction with environment
• How do we carry out geentic research?

  • twin studies
  • genomic studies
  • targeted mutations
• What are twin studies?

  Studies that compare the similarities and differences between identical and fraternal twins to determine the relative contributions of genetics and environment to certain traits or conditions
• What are genomic studies?

  Analysis of an organism's DNA to understand its genetic makeup and functions
• What are targeted mutations?

  • Mutated lab produced genes are inserted into chromosomes, two types:

  1. These can be defective and fail to produce a specific functional protein (“knockout genes”)
  2. These can also produce new or different proteins (“knock-in genes”)
• What is genetic engineering?

  the manipulation of an organism's genes to create desired traits or characteristics, can help treat diseases but unethical