- Kleefstra syndrome [DOID:0080597]
A syndrome that is characterized by developmental delay and intellectual disability, severely limited or absent speech, and weak muscle tone.
- spinal muscular atrophy type 0 [DOID:0080667]
A childhood spinal muscular atrophy that is evident before birth and characterized by diminished movement in the womb, joint deformities, extremely weak muscle tone and very weak respiratory muscles.
- partial trisomy distal 4q [DOID:0111159]
A chromosomal duplication syndrome characterized by growth deficiency, abnormal muscle tone, intellectual disability, and distinctive craniofacial malformations that has_material_basis_in duplication of the distal portion of chromosome 4q.
- Prader-Willi syndrome [DOID:11983]
A chromosomal disease that is characterized by weak muscle tone, feeding difficulties, poor growth, and delayed development. Beginning in childhood, affected individuals develop an insatiable appetite, which leads to chronic overeating and obesity.
- spastic cerebral palsy [DOID:0050669]
A cerebral palsy that is caused by damage in the outer layer of the brain, the cerebral cortex, which results in increased tone, or tension, in a muscle causing abnormal movements.
- Charcot-Marie-Tooth disease type 5 [DOID:0080067]
A Charcot-Marie-Tooth disease that is characterized by pyramidal features including extensor plantar responses, mild increase in tone, and preserved or increased reflexes but no spastic gait.
- nemaline myopathy [DOID:3191]
A congenital myopathy characterized by generally non-progressive muscle weakness of varying severity and problems with the tone and contraction of skeletal muscles. The muscle cells contain abnormal clumps of threadlike material called nemaline bodies.