| Inbound Relationships | Type | Active | Source | Characteristic | Refinability | Group | 
| [X]Severe mental retardation with the statement of no, or minimal, impairment of behavior | Is a | False | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| [X]Severe mental retardation, significant impairment of behavior requiring attention or treatment | Is a | False | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| [X]Severe mental retardation, other impairments of behavior | Is a | False | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| [X]Severe mental retardation without mention of impairment of behavior | Is a | False | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Profound intellectual disability (disorder) | Is a | False | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Severe intellectual disability, progressive postnatal microcephaly, midline stereotypic hand movements syndrome (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Severe intellectual disability and progressive spastic paraplegia | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Severe intellectual disability, progressive spastic diplegia syndrome (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Severe intellectual disability, hypotonia, strabismus, coarse face, planovalgus syndrome (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Fryns Smeets Thiry syndrome | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Severe intellectual disability, agenesis of corpus callosum, facial dysmorphism, cerebellar ataxia syndrome (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Keppen Lubinsky syndrome (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| 3-methylglutaconic aciduria type 9 | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Anterior maxillary protrusion, strabismus, intellectual disability syndrome (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Fatty acyl-coenzyme A reductase 1 deficiency (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Congenital insensitivity to pain with severe intellectual disability (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Craniosynostosis, microretrognathia, severe intellectual disability syndrome | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Posterior-predominant lissencephaly, broad flat pons and medulla-midline crossing defects syndrome | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Neurexin 1-related severe neurodevelopmental disorder, motor stereotypies, chronic constipation, sleep-wake cycle disturbance (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Congenital pontocerebellar hypoplasia type 14 | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| Microphthalmia with brain atrophy syndrome (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| X-linked intellectual disability, limb spasticity, retinal dystrophy, arginine vasopressin deficiency (disorder) | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  | 
| CCNK-related neurodevelopmental disorder, severe intellectual disability, facial dysmorphism syndrome | Is a | True | Severe intellectual disability (disorder) | Inferred relationship | Some |  |