Question: What is (are) Congenital central hypoventilation syndrome ?
Answer: Congenital central hypoventilation syndrome (CCHS) is a disorder of the autonomic nervous system that affects breathing. It causes a person to hypoventilate (especially during sleep), resulting in a shortage of oxygen and a buildup of carbon dioxide in the blood. Symptoms usually begin shortly after birth. Affected infants hypoventilate upon falling asleep and exhibit a bluish appearance of the skin or lips (cyanosis). Other features may include difficulty regulating heart rate and blood pressure; decreased perception of pain; low body temperature; sporadic profuse sweating; Hirschsprung disease; constipation; learning difficulties; eye abnormalities; and a characteristic facial appearance (having a short, wide, somewhat flattened face). CCHS is caused by a mutation in the PHOX2B gene and is inherited in an autosomal dominant manner. However, over 90% of cases are due to a new mutation in the affected person and are not inherited from a parent. Treatment typically includes mechanical ventilation or use of a diaphragm pacemaker.
Source: GARD

Question: What are the symptoms of Congenital central hypoventilation syndrome ?
Answer: What are the signs and symptoms of Congenital central hypoventilation syndrome? The Human Phenotype Ontology provides the following list of signs and symptoms for Congenital central hypoventilation syndrome. 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) Aganglionic megacolon 90% Apnea 90% Respiratory insufficiency 90% Short stature 90% Strabismus 90% Cognitive impairment 50% Muscular hypotonia 50% Seizures 50% Neuroblastoma 7.5% Oligohydramnios 7.5% Polyhydramnios 7.5% Prenatal movement abnormality 7.5% Sensorineural hearing impairment 7.5% Abnormality of temperature regulation - Abnormality of the cardiovascular system - Abnormality of the mouth - Autosomal dominant inheritance - Central hypoventilation - Constipation - Feeding difficulties - Ganglioneuroblastoma - Ganglioneuroma - Hyperhidrosis - Low-set ears - Posteriorly rotated ears - 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.
Source: GARD

Question: Is Congenital central hypoventilation syndrome inherited ?
Answer: How is congenital central hypoventilation syndrome inherited? Congenital central hypoventilation syndrome (CCHS) is inherited in an autosomal dominant manner. This means that having a change (mutation) in only one copy of the responsible gene in each cell is enough to cause features of the condition. The genetics of CCHS can be complex. Most people with CCHS have a new (de novo) mutation in the responsible gene (the PHOX2B gene). De novo mutations occur for the first time in the affected person and are not inherited from a parent. Some people with CCHS have a parent with the condition, and inherit the mutation from that parent. In some cases, an asymptomatic parent of a person with symptoms has a PHOX2B mutation in some of their germ cells (egg or sperm cells, not body cells). This is called germline mosaicism. Some of these parents also have a PHOX2B mutation in some of their body cells. This is called somatic mosaicism. Germline mosaicism with or without somatic mosaicism is present in about 25% of asymptomatic parents of people with CCHS. Parents with mosaicism should have a comprehensive assessment to determine if any features of CCHS are present. It is also recommended that parents of a person with a presumed de novo mutation have genetic testing for the presence of the mutation, including testing that detects mosaicism at low levels.
Source: GARD