A broader phenotype of autism: The clinical spectrum in twins

Ann Le Couteur, Anthony Bailey, Susan Goode, Andrew Pickles, Irving Gottesman, Sarah Robertson, Michael Rutter

Research output: Contribution to journalArticlepeer-review

352 Scopus citations


The diagnostic boundaries of the behavioural phenotype for autism were examined in 28 MZ pairs and 20 DZ same-sex twin pairs, where one or both twins had autism. In the nonautistic cotwin (i.e. in twin pairs discordant for autism) it was common to find language impairments in childhood and social deficits persisting into adulthood. Concordance for this broader phenotype was much greater in MZ pairs than DZ pairs, indicating a strong genetic component. Behavieural and cognitive manifestations of autism were compared both within and between MZ twin pairs. The variation was as great within MZ twin pairs as between pairs, suggesting that it does not index genetic heterogeneity (although aetiological heterogeneity probably exists). Current diagnostic practices need re-evaluation.

Original languageEnglish (US)
Pages (from-to)785-801
Number of pages17
JournalJournal of Child Psychology and Psychiatry and Allied Disciplines
Issue number7
StatePublished - Oct 1996


  • Autism
  • Broader phenotype
  • Genetics
  • Twins


Dive into the research topics of 'A broader phenotype of autism: The clinical spectrum in twins'. Together they form a unique fingerprint.

Cite this