Genetic Theory: Bio explanation 2 for sch

• Complement component 4 (C4)


  A gene that increases the risk of schizophrenia
• Synaptic pruning


  A process involving the elimination of connections between neurons, which happens naturally in the teen years
• Excessive or inappropriate amount of 'pruning'


  Could lead to the development of schizophrenia
• Schizophrenia symptoms often first appear during late adolescence
• MZ twins


  Identical twins
• DZ twins


  Fraternal twins
• If schizophrenia is caused by genetics

  The concordance rates for schizophrenia would be higher in MZ twins compared to DZ twins
• Gottesman et al found that the concordance rate for schizophrenia was higher for MZ twins by 48% compared to DZ twins by 17%
• Research from Joseph also supports the higher concordance rate for schizophrenia in MZ twins compared to DZ twins
• Gottesman found that the concordance rates for schizophrenia was higher in MZ twins by 48% than for DZ twins by 17%
• If schizophrenia is caused by genetics

  You would expect the concordance rate to be higher in MZ twins than for DZ twins
• The American Psychological Association showed that if one identical twin is affected by schizophrenia, there is a 40-60% chance their twin will suffer too, which reduces to 17% with non-identical twins
• Schizophrenia is most likely a polygenic disorder, determined by a number of different genes
• O'Donavan et al and his fellow researchers at Cardiff University identified 108 specific locations in the human genome that are likely to be linked to schizophrenia