Monarch Disease Ontology term MONDO_0009872 (Bjornstad syndrome) can be described as follows. Bjrnstad syndrome is characterized by congenital sensorineural hearing loss and pili torti. Less than fifty cases have been reported so far. The hearing loss usually becomes evident very early in life, often in the first year. Pili torti, a condition in which the hair shaft is flattened and twisted, makes the hair very brittle and patients develop hair loss in the first two years of life. Bjrnstad syndrome is transmitted as an autosomal recessive condition. It is caused by mutations in the BCS1L gene. Mutations in this gene also cause GRACILE syndrome. Also known as: Björnstad Syndrome, deafness-pili torti-hypogonadism syndrome.