answer:What are the signs and symptoms of Pontocerebellar hypoplasia type 1? Pontocerebellar hypoplasia type 1 (PCH1) may first present in the prenatal period with reduced fetal movement. Polyhydramnios may also be noted. In most cases, the condition is obvious in the newborn period when respiratory insufficiency and muscle weakness present. Multiple contractures may also be present at birth, along with other motor impairment. Mental retardation and other signs of cerebellar disruption, including visual impairment, nystagmus and ataxia, may follow the initial presentation. The Human Phenotype Ontology provides the following list of signs and symptoms for Pontocerebellar hypoplasia type 1. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Aplasia/Hypoplasia of the cerebellum 90% Cerebral cortical atrophy 90% Hypertonia 90% Limitation of joint mobility 90% Microcephaly 90% Seizures 90% Deviation of finger 50% Abnormality of the foot - Ataxia - Autosomal recessive inheritance - Basal ganglia gliosis - Cerebellar hypoplasia - Congenital contracture - Congenital onset - Degeneration of anterior horn cells - EMG: neuropathic changes - Fasciculations - Feeding difficulties in infancy - Hyperreflexia - Hypoplasia of the pons - Hypoplasia of the ventral pons - Intellectual disability - Muscle weakness - Muscular hypotonia - Neuronal loss in basal ganglia - Progressive - Respiratory insufficiency - Spinal muscular atrophy - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.

answer:What causes pontocerebellar hypoplasia type 1? A specific mutations in the VRK1 gene has caused PCH1 in at least one family. Specific mutations in RARS2 and TSEN54 have also been associated with PCH1. TSEN54 mutations were identified in one case from a family with three siblings with PCH1; DNA was only available in one of the three siblings. Mutations in RARS2 were also identified in one case with PCH1. In general, there is no known genetic cause for the majority of PCH1 cases and no other genes have been linked to PCH1 yet, with the exception of rare cases associated with TSEN54, RARS2 and VRK1 mutations. In fact, only fifteen families with PCH1 have been published thus far; of these, mutations were only identified in 3 families. Further research on these and other candidate genes in PCH1 is necessary to identify mutations involved in the remaining majority of the PCH1 cases.Specific mutations in other genes have been shown to cause the various other forms of pontocerebellar hypoplasia and include the RARS2, TSEN2, TSEN34, and TSEN54 genes. Mutations in three related genes, TSEN2, TSEN34, and TSEN54, can result in PCH2. TSEN54 gene mutations can also cause PCH4 and PCH5.[2951] Mutations in the RARS2 gene can cause PCH6. The genetic cause of PCH3 is unknown.

answer:How is pontocerebellar hypoplasia type 1 inherited? Pontocerebellar hypoplasia type 1 (PCH1) is inherited in an autosomal recessive pattern, which means both copies of the associated gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. This means that parents who are carriers of this condition have a 25% chance of having an affected child.

answer:How might pontocerebellar hypoplasia type 1 be treated? There is no standard therapy for pontocerebellar hypoplasia type 1. Treatment is symptomatic and supportive.