Genetic Explanation

• Genes - DNA
• Instructions - Blueprints for building organisms - Cells, organs, tissues
• Heritability - The extent a characteristic is passed to offspring
• 50% biological mother 50% biological father
• Mental illness has an organic cause which is passed on through DNA
• 5-HTT - Seratonin transporter gene (regulates seratonin levels)
• Alleles - These are different versions of the same gene, there are two versions in 5-HTT long and short
• Long alleles are believed to be more efficient at producing seratonin
• SS are less resilient to stress, so more likely to suffer from depression
• Brain abnormality - The brain of those with mental illness is physically different in size or activity levels.
• Depression - Frontal lobes - Area involved in thinking, depressed patients have significantly smaller volume.
• Cortisal - Is a by product of stress response (flight or fight)

  It destroys hippocampus cells (depression 25% less)

  Hippocampus regulates seratonin levels
• Activity - Blood flow is less (abnormal) in frontal lobes of depressed patients