Biotinidase Deficiency (BIOT)



Biotinidase deficiency (BIOT) is an inherited genetic condition in which the body is unable to reuse and recycle the vitamin biotin. Since the body needs free biotin to break down fats, proteins, and carbohydrates effectively; individuals with BIOT are less able to process important nutrients. There are two main types of BIOT, each differing in the severity of signs — severe “profound biotinidase deficiency” and mild “partial biotinidase deficiency.” Babies who are identified through newborn screening as having BIOT and begin treatment immediately usually remain healthy with normal development. Signs of BIOT usually start within a few months after birth. In some cases, symptoms may not appear until childhood. Early signs of BIOT include seizures (epilepsy), weak muscle tone (hypotonia), trouble breathing, skin rash, hair loss, trouble balancing, and a fungal infection called candidiasis.

Condition Type:

Core Conditions


Biotinidase deficiency (BIOT) occurs in 1 out of every 60,000 births. The condition is most common among individuals of European descent. However, it is also reported among individuals of Turkish, Saudi Arabian, and Japanese descent.

More Information for Parents:
Also known as:
  • BIOT
  • BTD deficiency
  • Late-Onset biotin-responsive multiple carboxylase deficiency
  • Late-Onset multiple carboxylase deficiency

Core Conditions