Inclusion Criteria:

• for patients:

  • being included in the main study "C16-89 - Study of genetic factors involved in ASD and related disorders"
  • having an ASD fulfilling DSM-5 diagnostic criteria (APA, 2012). Diagnosis will be done by a clinical expert, with the support of structured instruments (ADI-R, ADOS-2)
  • having at least 24 Months
  • being affiliated with the French health insurance
  • having signed the informed consent (by proposant or by legal tutors if the subject is <18 or under legal custody)

• for relatives

  • being included in the main study "C16-89 - Study of genetic factors involved in ASD and related disorders"
  • having at least 24 Months
  • being affiliated with the French health insurance
  • having signed the informed consent (by proposant or by legal tutors if the subject is <18 or under legal custody)

• for controls

  • being included in the main study "C16-89 - Study of genetic factors involved in ASD and related disorders"
  • having at least 24 Months
  • being affiliated with the French health insurance
  • having signed the informed consent (by proposant or by legal tutors if the subject is <18 or under legal custody)

Non-inclusion criteria:

• for all subjects

  • severe mental retardation (IQ<35 or developmental age<18 months)
  • medical condition (either psychiatric or physical) not compatible with an inclusion
  • MRI counter indication
  • Current pregnancy or breastfeeding, assessed by questionnaire
  • Not willing to be informed of a brain abnormality diagnosed with MRI

• for the relatives

  *discovery of non filiation during the genetic analyses

• for controls

  • Neurological history (except mental retardation)
  • Personal history of (checked with DIGS for Adults, Diagnostic Interview for Genetic Studies, Numberger et coll., 1994, or Kiddie SADS, Kiddie Schedule for Disorders and Schizophrenia for School Age Children, Orvaschel et coll., 1982): schizophrenia, addiction, bipolar disorder, recurrent depression (> 2 episodes lifetime), severe, not stabilized anxiety disorder, history of episodes of epilepsy, significant inflammatory disease of immunosuppressive medication

Exclusion Criteria:

• for patients: ASD diagnosis not confirmed by assessments after the inclusion
• for all subjects: discovery of a counter indication to MRI during the exam (e.g. claustrophobia)