1.4. Monogenetic Neurodevelopmental Disorders
Fragile X syndrome (FXS), a result of the loss-of-function of the Frmr1
gene, and Rett’s syndrome, linked to a loss of function in the Mecp2
gene, are complex neurodevelopmental disorders with some overlapping
features \cite{RN38}, that both show a high
co-morbidity with a diagnosis of ASD \cite{RN39,RN40,RN41,RN42}. Multiple animal models have been generated of these disorders \cite{RN40,RN44,RN43,RN45} and although these syndromes do
result from single gene mutations, their endophenotypic manifestation
can be complex and difficult to unravel. Nonetheless, the numerous
studies which have detailed the impact of each mutation at levels
ranging from synapses to behavior make them an important asset to
understanding how ASD alters hippocampal function.