Neuroanatomical and neurocognitive differences in a pair of monozygous twins discordant for strictly defined autism.

TitleNeuroanatomical and neurocognitive differences in a pair of monozygous twins discordant for strictly defined autism.
Publication TypeJournal Article
Year of Publication1998
AuthorsKates WR, Mostofsky SH, Zimmerman AW, Mazzocco MM, Landa R, Warsofsky IS, Kaufmann WE, Reiss AL
JournalAnnals of neurology
Volume43
Issue6
Pagination782-91
Date Published1998 Jun
Abstract

In this study, we investigated the neuroanatomical similarities and differences between a pair of monozygotic, 7.5-year-old twin boys discordant for strictly defined autism, to identify neuroanatomical pathways that are impaired in individuals with autism. Although the unaffected twin did not fulfill the traditional diagnostic criteria for autism, he displayed constrictions in social interaction and play that were consistent with the broader phenotype for autism that has been described in nonautistic co-twins. Magnetic resonance imaging scans were obtained for each brother and compared with the scans of 5 age- and sex-matched unaffected peers. Quantitative analysis of brain anatomy revealed that the affected twin had markedly smaller caudate, amygdaloid, and hippocampal volumes, and smaller cerebellar vermis lobules VI and VII, in comparison with his brother. Both twins evidenced disproportionately reduced volumes of the superior temporal gyrus and the frontal lobe relative to the comparison sample. The results suggest the dysfunction of two separate but overlapping neuroanatomical pathways, ie, one subcortical network differentiating the twins from each other that may underlie the traditional neurobehavioral phenotype for strictly defined autism, and a second cortical network differentiating the twins from the comparison sample that may lead to the broader phenotype for autism.

DOI10.1371/journal.pone.0050430
Alternate JournalAnn. Neurol.