Total 22 clinical symptoms reported for Sphingolipid activator protein 1 deficiency  Very Frequent (9)Not Applicable Or Unknown (13)

Developmental regression	Loss of developmental skills, as manifested by loss of developmental milestones.   Synonyms:Loss of acquired milestones; Loss of developmental milestones; Loss of milestones; Mental deterioration in childhood; Neurodevelopmental regression; Psychomotor regression; Psychomotor regression beginning in infancy; Psychomotor regression in infants; Psychomotor regression, progressive	Very frequent
Global developmental delay	A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.   Synonyms:Delayed cognitive development; Delayed development; Delayed developmental milestones; Delayed intellectual development; Delayed milestones; Delayed psychomotor development; Developmental delay; Developmental delay in early childhood; Developmental delay, global; Developmental retardation; GDD; Lack of psychomotor development; Motor and developmental delay; Motormental retardation; Psychomotor delay; Psychomotor development deficiency; Psychomotor development failure; Psychomotor developmental delay; Retarded development; Retarded mental development; Retarded psychomotor development	Very frequent
Hypotonia	Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.   Synonyms:Low muscle tone; Low or weak muscle tone; Muscle hypotonia; Muscular hypotonia	Very frequent
Loss of ambulation	Inability to walk in a person who previous had the ability to walk.   Synonyms:Loss of ability to walk	Very frequent
Motor deterioration	Loss of previously present motor (i.e., movement) abilities.   Synonyms:Progressive degeneration of movement	Very frequent
Muscle weakness	Reduced strength of muscles.   Synonyms:Muscle weakness; Muscular weakness	Very frequent
Peripheral demyelination	A loss of myelin from the internode regions along myelinated nerve fibers of the peripheral nervous system.   Synonyms:Demyelination	Very frequent
Peripheral neuropathy	Peripheral neuropathy is a general term for any disorder of the peripheral nervous system. The main clinical features used to classify peripheral neuropathy are distribution, type (mainly demyelinating versus mainly axonal), duration, and course.   Synonyms:Peripheral nerve damage; Peripheral neuritis	Very frequent
Polyneuropathy	A generalized disorder of peripheral nerves.   Synonyms:Peripheral nerve disease	Very frequent