Congenital hypertrichosis lanuginosa is a rare disorder characterized by excessive lanugo hair present at birth covering the entire body surface except the mucosae, palms, and soles (summary by De Raeve and Keymolen, 2011).

Developmental and epileptic encephalopathy-23 (DEE23) is an autosomal recessive neurologic disorder characterized by the onset of intractable seizures in the first months of life (range, 2-6 months). Affected individuals have severely impaired psychomotor development with poor or absent speech, cortical blindness, and dysmorphic facial features (summary by Perrault et al., 2014).