SNP Shot: Genomic Insights

Biotinidase deficiency is a genetic condition where the body struggles to reuse the vitamin biotin. Without diagnosis and treatment, symptoms usually emerge in early infancy, but can appear later in childhood.

In profound biotinidase deficiency, the more serious type, individuals may experience seizures, low muscle tone (hypotonia), respiratory issues, hearing and vision impairment, coordination and balance difficulties (ataxia), skin rashes, hair loss (alopecia), and candidiasis (a fungal infection). Developmental delays are also common. With consistent, lifelong treatment, these complications can be prevented or lessened if already present.

Partial biotinidase deficiency is a less severe form. Children with this form may develop hypotonia, skin rashes, and hair loss if untreated, but these symptoms often only appear during periods of illness, infection, or stress.

Inheritance:

Biotinidase deficiency follows an autosomal recessive inheritance pattern. This means that both copies of the BTD gene in each cell must have mutations for the condition to manifest. Individuals with biotinidase deficiency inherit one mutated copy of the gene from each parent, who are typically carriers and do not exhibit symptoms of the condition.