Heric cerebellum need to be deemed for every patient with ID presenting with strabismus, seizures and deep set eyes. In parallel, a molecular screening for sequence mutations and structural genomic rearrangements of OPHN1 needs to be performed. Additionally, cautious comparison with the OPHN1 mutation together with the observed phenotype can supply insight in to the etiopathological mechanisms underlying XLID and the function of your impacted protein domain. CONFLICT OF INTEREST The authors declare no conflict of interest. ACKNOWLEDGEMENTSWe thank the members of the family for their kind cooperation, `Centro Estadual de ?Diagnostico por Imagem’ (SES, Rio de Janeiro, Brazil) for conducting the neuroimaging tests and Professor Paulo Luciano Gomes for assisting in the EEG procedures. This work was supported by funds from CNPq (473824/2011-6), FAPERJ (E-26/103.215/2011), PPSUS-MS/CNPq/FAPERJ (E-26/110.765/2010) and CEPUERJ.1 Larson SA, Lakin KC, Anderson L, Kwak N, Lee JH, Anderson D: Prevalence of mental retardation and developmental disabilities: estimates from the 1994/1995 National Wellness Interview Survey Disability Supplements. Am J Ment Retard 2001; 106: 231?52. 2 Tolias KF, Duman JG, Um K: Manage of synapse improvement and plasticity by Rho GTPase regulatory proteins. Prog Neurobiol 2011; 94: 133?48. 3 Bienvenu T, Der-Sarkissian H, Billuart P et al: Mapping of your X-breakpoint involved inside a balanced X;12 translocation within a female with mild mental retardation. Eur J Hum Genet 1997; 5: 105?09. 4 Billuart P, Bienvenu T, Ronce N et al: Oligophrenin-1 encodes a rhoGAP protein involved in X-linked mental retardation. Nature 1998; 392: 923?26. five Al-Owain M, Kaya N, Al-Zaidan H et al: Novel intragenic deletion in OPHN1 in a household causing XLMR with cerebellar hypoplasia and distinctive facial look. Clin Genet 2011; 79: 363?70. 6 Pirozzi F, Di Raimo FR, Zanni G et al: Insertion of 16 amino acids in the BAR domain on the oligophrenin 1 protein causes mental retardation and cerebellar hypoplasia in an Italian household. Hum Mutat 2011; 32: E2294 2307. 7 Fauchereau F, Herbrand U, Chafey P et al: The RhoGAP activity of OPHN1, a new F-actin-binding protein, is negatively controlled by its amino-terminal domain. Mol Cell Neurosci 2003; 23: 574?86. eight Govek EE, Newey SE, Akerman CJ, Cross JR, Van der Veken L, Van Aelst L: The X-linked mental retardation protein oligophrenin-1 is essential for dendritic spine morphogenesis. Nat Neurosci 2004; 7: 364?72. 9 Khelfaoui M, Denis C, van Galen E et al: Loss of X-linked mental retardation gene oligophrenin 1 in mice impairs spatial memory and results in ventricular enlargement and dendritic spine immaturity.1H-Pyrrole-2-carbonitrile web J Neurosci 2007; 27: 9439?450.1416444-91-1 Chemical name ten Kasri NN, Nakano-Kobayashi A, Malinow R, Li B, Van Aelst L: The Rho-linked mental retardation protein oligophrenin-1 controls synapse maturation and plasticity by stabilizing AMPA receptors.PMID:33608408 Genes Dev 2009; 23: 1289?302.11 Khelfaoui M, Pavlowsky A, Powell AD et al: Inhibition of RhoA pathway rescues the endocytosis defects in oligophrenin 1 mouse model of mental retardation. Hum Mol Genet 2009; 18: 2575?583. 12 Santos CB, Pimentel MMG: The influence of expanded unmethylated alleles for FRAXA/FRAXE loci inside the intellectual overall performance amongst Brazilian mentally impaired males. Int J Mol Med 2003; 12: 385?89. 13 Froyen G, Belet S, Martinez F et al: Copy-number gains of HUWE1 as a consequence of replication- and recombination-based rearrangements. Am J Hum Genet 2012; 91: 252?64. 14 Busque L, Paquette Y, Provo.