Evaluation

• Key points

  • Research support
  • Complexity
  • Real-world applications
• Research support

  • Colvert et al 2015 conducted a study using twins from TEDs which includes all twins born in Eng + Wales between 1994+96
  • They assessed autistic traits in over 6423 twin pairs aged 8 or older using questionnaire, checklist, observations + interviews
• Research support 2

  • The concordance rates for ASD in identical twins (Mz) ranged from 0.77 to 0.99 + from non-identical twins (Dz) from 0.22 to 0.65. The researchers estimated that genetic factors contribute from 56% to 95% to the development of both clinically diagnosed ASD + the broader autistic traits found in the general population, according to measure used
  • This evidence strongly indicates that genetics play a significant role in development of both diagnosed ASD + the borader autistic traits found in the general population
• Complexity

  • ASD is a complex disorder with various traits, like social, cognitive + communicative aspects
  • Some of these traits are influenced more by genes than others, meaning certain genetic variants increase vulnerability to ASD, but no single gene alone causes the disorder
• Complexity 2

  • Benvenuto (2009) identified around ten candidate genes that play roles in the development + functioning of the nervous system, including how neurons connect with each other. These nervous system abnormalities could lead to ASD symptoms. According to their research, about 90% of ASD is likely to be caused by multiple genes interacting with each other + with environmental factors
  • No clear-cut genetic explanation for the majority of ASD cases
• Real-world applications:

  • A better understanding of the causes of ASD brings hope for earlier diagnosis and more effective interventions
  • Early detection can help families prepare for challenges a child with ASD may face through genetic counselling, offer more options for timely interventions + spare families the long and stressful process of diagnostic journey
• Incomplete explanations

  • Cannot completely dismiss the impact of environmental factors on ASD
  • The diathesis-stress model suggests ASD arises from the combination of a genetic predisposition (diathesis) + an early detrimental influence on the developing brain
• Incomplete explanations

  • Landrigan (2010) points out several possible environmental triggers that could interact with a genetic predisposition - e.g = prenatal influences like exposure to harmful chemicals during early pregnancy