Question: What is (are) Harlequin ichthyosis ?
Answer: Harlequin ichthyosis is a severe genetic disorder that mainly affects the skin. The newborn infant is covered with plates of thick skin that crack and split apart. The thick plates can pull at and distort facial features and can restrict breathing and eating. Mutations in the ABCA12 gene cause harlequin ichthyosis. This condition is inherited in an autosomal recessive pattern.
Source: GARD

Question: What are the symptoms of Harlequin ichthyosis ?
Answer: What are the signs and symptoms of Harlequin ichthyosis? The Human Phenotype Ontology provides the following list of signs and symptoms for Harlequin ichthyosis. 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) Abnormality of the eyelid 90% Depressed nasal ridge 90% Hearing abnormality 90% Hyperkeratosis 90% Recurrent respiratory infections 90% Abnormality of the mouth 50% Limitation of joint mobility 50% Cataract 7.5% Dehydration 7.5% Foot polydactyly 7.5% Hand polydactyly 7.5% Malignant hyperthermia 7.5% Respiratory insufficiency 7.5% Self-injurious behavior 7.5% Sudden cardiac death 7.5% Autosomal recessive inheritance - Congenital ichthyosiform erythroderma - Ectropion - Premature birth - Proptosis - Rigidity - Short finger - 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