MedGen

Platelet-type bleeding disorder-17 is an autosomal dominant disorder characterized by increased bleeding tendency due to abnormal platelet function. It is a type of 'gray platelet syndrome' because the platelets appear abnormal on light microscopy. Electron microscopy shows decreased or absent alpha-granules within platelets, and bone marrow biopsy shows increased numbers of abnormal megakaryocytes, suggesting a defect in megakaryopoiesis and platelet production. The bleeding severity is variable (summary by Monteferrario et al., 2014). [from OMIM]

Spasticity and weakness of the leg and hip muscles. [from HPO]

Severe or complete weakness of both lower extremities with sparing of the upper extremities. [from HPO]

A genetically and clinically heterogeneous group of slowly progressive neurological disorders which in the pure form is characterized by pyramidal signs (weakness, spasticity, brisk tendon reflexes, and extensor plantar responses) predominantly affecting the lower limbs and with possible association of sphincter disturbances and deep sensory loss; and in the complex form by the addition of variable neurological or non-neurological features. [from ORDO]

A type of ataxia characterized by the impairment of the ability to smoothly perform the elements of a voluntary movement in the appropriate order and speed. With dyssynergia, a voluntary movement appears broken down into its component parts. [from HPO]

A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. [from HPO]

Contractures, pterygia, and spondylocarpotarsal fusion syndrome-1A (CPSFS1) is characterized by contractures of proximal and distal joints, pterygia involving the neck, axillae, elbows, and/or knees, as well as variable vertebral, carpal, and tarsal fusions and short stature. Progression of vertebral fusions has been observed, and inter- and intrafamilial variability has been reported (Carapito et al., 2016; Zieba et al., 2017; Cameron-Christie et al., 2018). An autosomal recessive form of CPSFS (CPSFS1B; 618469) is caused by compound heterozygous mutation in the MYH3 gene. [from OMIM]

Abnormal cognition is characterized by deficits in thinking, reasoning, or remembering. [from HPO]

Spastic paraplegia 11 (SPG11) is characterized by progressive spasticity and weakness of the lower limbs frequently associated with the following: mild intellectual disability with learning difficulties in childhood and/or progressive cognitive decline; peripheral neuropathy; pseudobulbar involvement; and increased reflexes in the upper limbs. Less frequent findings include: cerebellar signs (ataxia, nystagmus, saccadic pursuit); retinal degeneration; pes cavus; scoliosis; and parkinsonism with characteristic brain MRI features that include thinning of the corpus callosum. Onset occurs mainly during infancy or adolescence (range: age 1-31 years) and in rare cases as late as age 60 years. Most affected individuals become wheelchair bound one or two decades after disease onset. [from GeneReviews]

A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. [from HPO]

A rare, small-vessel vasculitis characterized by skin purpura, arthritis, abdominal and/or renal involvement, IgA tissue deposits (arterioles, capillaries, and venules) and circulating IgA immune complexes. [from ORDO]

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. [from HPO]

A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes. [from HPO]

Spasticity (velocity-dependent increase in tonic stretch reflexes with increased muscle tone and hyperexcitable tendon reflexes) in the muscles of the lower limbs, hips, and pelvis. [from HPO]

Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly). [from HPO]

An abnormality of the nervous system. [from HPO]

Inflammation or degeneration of the peripheral motor nerves. [from MONDO]

A generalized disorder of peripheral nerves. [from HPO]

A group of slowly progressive inherited disorders affecting motor and sensory peripheral nerves. Subtypes include HMSNs I-VII. HMSN I and II both refer to CHARCOT-MARIE-Tooth DISEASE. HMSN III refers to hypertrophic neuropathy of infancy. HMSN IV refers to REFSUM DISEASE. HMSN V refers to a condition marked by a hereditary motor and sensory neuropathy associated with spastic paraplegia (see SPASTIC PARAPLEGIA, HEREDITARY). HMSN VI refers to HMSN associated with an inherited optic atrophy (OPTIC ATROPHIES, HEREDITARY), and HMSN VII refers to HMSN associated with retinitis pigmentosa. (From Adams et al., Principles of Neurology, 6th ed, p1343) [from MONDO]

Hereditary motor and sensory neuropathies (HMSN) are a heterogeneous group of peripheral nervous system disorders affecting motor and sensory function. HMSN I, also known as Charcot-Marie-Tooth (CMT) disease, or peroneal muscular atrophy, type 1, is a demyelinating neuropathy (see CMT1B; 118200) and HMSN II, also known as CMT type 2, is an axonal neuropathy (see CMT2A1; 118210). See also HMSN III (145900) and HMSN IV (266500). For an autosomal recessive disorder with similarities to HMSN V, see 607731. [from OMIM]