Biotidinase Deficiency ( BTD) gene sequencing

Biotinidase Deficiency (BTD) Gene Sequencing

Biotinidase Deficiency is a rare inherited metabolic disorder caused by mutations in the BTD gene. This condition affects the body’s ability to recycle biotin (Vitamin B7), an essential vitamin required for healthy metabolism, nervous system function, skin, and hair health.

Why is this test done?

BTD gene sequencing helps identify mutations associated with biotinidase deficiency and is recommended for:

• Newborns with abnormal metabolic screening results
• Individuals with seizures, developmental delay, hearing loss, or skin rash
• Unexplained neurological symptoms
• Family history of biotinidase deficiency
• Carrier screening for couples planning pregnancy

Symptoms of Biotinidase Deficiency

Symptoms may vary from mild to severe and can include:

• Seizures
• Weak muscle tone (hypotonia)
• Breathing difficulties
• Hair loss (alopecia)
• Skin rashes
• Developmental delay
• Vision or hearing problems
• Coordination difficulties

About the Test

• Sample Required: Blood sample
• Method: Next Generation Sequencing (NGS) / Sanger Sequencing
• Gene Analyzed: BTD gene
• Purpose: Detect pathogenic mutations linked to biotinidase deficiency

Benefits of Early Detection

Early diagnosis allows timely treatment with biotin supplementation, which can prevent irreversible neurological damage and significantly improve quality of life.

Who should consider this test?

• Infants with positive newborn screening
• Children with unexplained neurological symptoms
• Siblings of affected individuals
• Couples seeking genetic counseling

Turnaround Time

Typically 2–4 weeks, depending on laboratory workflow.

Interpretation

Results should always be interpreted along with:

• Clinical findings
• Enzyme activity levels
• Family history
• Genetic counseling recommendations

Early genetic testing plays a crucial role in preventing long-term complications and supporting personalized treatment decisions.