title: Non-syndromic X-linked mental retardation: from a molecular to a clinical point of view.
abstract: This review focuses on the 19 identified genes involved in X-linked "non-syndromic" mental retardation (MR) and defines the signaling pathways in which they are involved, focusing on emerging common mechanisms. The majority of proteins are involved in three distinct pathways: (1) Rho GTPases pathway modulating neuronal differentiation and synaptic plasticity; (2) Rab GTPases pathway regulating synaptic vesicle cycling; (3) gene expression regulation. The function of four proteins (ACSL4, AT2, SLC6A8, and SAP102) could not be reconciled to a common pathway. From a clinical point of view, the review discusses whether some common dysmorphic features can be identified even in non-syndromic MR patients and whether it is correct to maintain the distinction between "non-syndromic" and "syndromic" MR.
authors.affiliation: Medical Genetics, Department of Molecular Biology, University of Siena, Siena, Italy. renieri@unisi.it
authors.forename: A
authors.initials: A
authors.lastname: Renieri
authors.forename: C
authors.initials: C
authors.lastname: Pescucci
authors.forename: I
authors.initials: I
authors.lastname: Longo
authors.forename: F
authors.initials: F
authors.lastname: Ariani
authors.forename: F
authors.initials: F
authors.lastname: Mari
authors.forename: I
authors.initials: I
authors.lastname: Meloni
mesh_terms: D041321:Chromosomes, Human, X / Q000235:genetics*; D005786:Gene Expression Regulation; D006801:Humans; D038901:X-Linked Intellectual Disability / Q000235:genetics* / Q000473:pathology*; D009473:Neuronal Plasticity / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics