Aarskog Syndrome; Abidi Syndrome; Adrenoleukodystrophy; Ahmad Syndrome; Aicardi Syndrome; Allan-Herndon-Dudley Syndrome; Alpha-Thalassemia Intellectual Disability (see also ATRX-Associated XLID); AP1S2-Associated XLID; Apak Ataxia-Spastic Diplegia Syndrome; Arena Syndrome (see Pelizaeus-Merzbacher Syndrome); Armfield Syndrome; Arts Syndrome; ARX-Associated XLID; Ataxia-Deafness-Dementia, X-linked; Atkin-Flaitz Syndrome; ATRX-Associated XLID; Bergia Cardiomyopathy; Bertini Syndrome; B?rjeson-Forssman-Lehmann Syndrome; Branchial Arch Syndrome, X-Linked; Cantu Syndrome; Carpenter-Waziri Syndrome (see also ATRX-Associated XLID); Cerebro-Cerebello-Coloboma Syndrome; Cerebro-Oculo-Genital Syndrome; Cerebro-Palato-Cardiac Syndrome (see also Renpenning Syndrome); Charcot-Marie-Tooth Neuropathy, Cowchock Variant; Charcot-Marie-Tooth Neuropathy, Ionasescu Variant; Chassaing-Lacombe Chondrodysplasia; Christian Syndrome; Christianson Syndrome; Chudley-Lowry Syndrome (see also ATRX-Associated XLID); CK Syndrome; Clark-Baraitser Syndrome; Coffin-Lowry Syndrome; Cornelia de Lange Syndrome, X-Linked; Craniofacioskeletal; Duchenne Muscular Dystrophy; Dyskeratosis Congenita; Epilepsy-Intellectual Disability in Females; Fitzsimmons Syndrome; FLNA-Associated XLID; Fragile X Syndrome; Giuffr?-Tsukahara Syndrome; Glycerol Kinase Deficiency; Golabi-Ito-Hall Syndrome (see also Renpenning Syndrome); Goldblatt Spastic Paraplegia Syndrome; Goltz Syndrome; Graham Anophthalmia Syndrome; Gustavson Syndrome; Hall Orofacial Syndrome; Hereditary Bullous Dystrophy, X-Linked; Holmes-Gang Syndrome (see also ATRX-Associated XLID); Homfray Seizures-Contractures; Hyde-Forster Syndrome; Hydranencephaly with Abnormal Genitalia; Hydrocephaly-Cerebellar Agenesis Syndrome; Hydrocephaly-MASA Spectrum; Hypoparathyroidism, X-Linked; Incontinentia Pigmenti; Juberg-Marsidi-Brooks; Kang Syndrome; Lenz Microphthalmia Syndrome; Lesch-Nyhan Syndrome; Lissencephaly and Abnormal Genitalia, X-Linked (see also ARX-Associated XLID); Lissencephaly, X-Linked; Lowe Syndrome; Lujan Syndrome; MEHMO Syndrome; Menkes Syndrome; MIDAS Syndrome; Miles-Carpenter Syndrome; Mohr-Tranebjaerg Syndrome; Monoamine Oxidase-A Deficiency; Mucopolysaccharidosis IIA; Myotubular Myopathy; Nance-Horan Syndrome; Norrie Disease; Optic Atrophy, X-Linked; Opitz FG Syndrome; Oral-Facial-Digital Syndrome I; Ornithine Transcarbamoylase Deficiency; Otopalatodigital Syndrome I (see also FLNA-Associated XLID); Otopalatodigital Syndrome II (see also FLNA-Associated XLID); Paine Syndrome; Pallister W Syndrome; Partington Syndrome (see also ARX-Associated XLID); Pelizaeus-Merzbacher Syndrome; Periventricular Nodular Heterotopia (see also FLNA-Associated XLID); Pettigrew Syndrome; Phosphoglycerate Kinase Deficiency; Plott Syndrome; Porteous Syndrome (see also Renpenning Syndrome); PPM-X; Prieto Syndrome; Proud Syndrome (see also ARX-Associated XLID); Pyruvate Dehydrogenase Deficiency; Renpenning Syndrome; Rett Syndrome; Rett-like Seizures-Hypotonia; Roifman Syndrome; Say-Meyer Syndrome; Schimke Syndrome; Shashi Syndrome; Shrimpton Syndrome; Simpson-Golabi-Behmel Syndrome; Smith-Fineman-Myers Syndrome; Snyder-Robinson Syndrome; Stocco dos Santos Syndrome; Stoll Syndrome; Sutherland-Haan Syndrome (see also Renpenning Syndrome); Telecanthus-Hypospadias Syndrome; Turner XLID; Urban Syndrome; VACTERL-Hydrocephalus Syndrome; Vasquez Syndrome; Waisman-Laxova Syndrome; Warkany Syndrome; Wieacker-Wolff Syndrome; Wilson-Turner Syndrome; Wittwer Syndrome; XLID-Agenesis of the Corpus Callosum; XLID-Arch Fingerprints-Hypotonia Syndrome (see also ATRX-Associated XLID); XLID-Ataxia-Apraxia; XLID-Ataxia-Dementia; XLID-Blindness-Seizures-Spasticity; XLID-Choreoathetosis; XLID-Choroideremia-Ectodermal Dysplasia; XLID-Cleft Lip/Cleft Palate; XLID-Epilepsy (XIDE); XLID-Hydrocephaly-Basal Ganglia Calcifications (see also AP1S2-Associated XLID); XLID-Hypogammaglobulinemia; XLID-Hypogonadism-Tremor; XLID-Hypospadias; XLID-Hypotonia-Recurrent Infections; XLID-Ichthyosis-Hypogonadism; XLID-Infantile Spasms (see also ARX-Associated XLID); XLID-Isolated Growth Hormone Deficiency; XLID-Macrocephaly; XLID-Macrocephaly-Macroorchidism; XLID-Microcephaly-Testicular Failure; XLID-Nail Dystrophy-Seizures; XLID-Nystagmus-Seizures; XLID-Optic Atrophy; XLID-Panhypopituitarism; XLID-Precocious Puberty; XLID-Psoriasis; XLID-Retinitis Pigmentosa; XLID-Rolandic Seizures; XLID-Spastic Paraplegia, Type 7; XLID-Spastic Paraplegia-Athetosis; XLID-Spondyloepimetaphyseal Dysplasia; XLID-Thyroid Aplasia-Cutis Verticis Gyrata; XLID-Thyroxine-Binding Globulin Deficiency; Young-Hughes Syndrome; Appendices; I. Genes Involved in X-Linked Intellectual Disability (by order of discovery); II. XLID Syndromes with Microcephaly; III. XLID Syndromes with Macrocephaly; IV. XLID Syndromes with Ocular Anomalies and/or Visual Impairment; V. XLID Syndrome with Hearing Loss; VI. XLID Syndromes with Facial Clefting; VII. XLID Syndromes with Cardiac Malformations or other Cardiovascular Abnormalities; VIII. XLID Syndromes with Urogenital Anomalies; IX. XLID Syndromes with Neuronal Migration Disturbance; X. XLID Syndromes with Spastic Paraplegia; XI. XLID Syndromes with Seizures; XII. XLID Syndromes with Hypotonia; XIII. XLID Syndromes Predominately Affecting Females; XIV. Duplication of XLID Genes and Regions of the X Chromosome Genome; XV. Non-Syndromal XLID Families; XVI. X-Inactivation in Heterozygous Females