A peroxisomal disease characterized by, in severe cases, infantile-onset of hypotonia, seizures, and abnormal facial features with most dying before age 2 years that has_material_basis_in homozygous or compound heterozygous mutation in the HSD17B4 gene on chromosome 5q2. [ url:https://ghr.nlm.nih.gov/condition/d-bifunctional-protein-deficiency http://purl.obolibrary.org/obo/ECO_0007636 http://purl.obolibrary.org/obo/ECO_0007637 url:https://www.omim.org/entry/261515 ]