SLC52A3 gene
The SLC52A3 gene provides instructions for a riboflavin transporter protein essential for absorbing vitamin B2 during digestion.
Normal Function
The SLC52A3 gene provides instructions for making a riboflavin transporter protein called RFVT3. Because the body cannot produce riboflavin (vitamin B2) on its own, it must be obtained through diet. The RFVT3 protein is found at high levels in the small intestine, where it transports riboflavin across the cell membrane for absorption.
Inside the body's cells, riboflavin is a core component of flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN). These molecules function as coenzymes, helping enzymes carry out chemical reactions necessary for:
- Producing energy for cells
- Breaking down (metabolizing) carbohydrates, fats, and proteins
Health Conditions Related to Genetic Changes
Riboflavin transporter deficiency neuronopathy
Mutations in the SLC52A3 gene cause riboflavin transporter deficiency neuronopathy, a neurological condition that encompasses what were previously considered two separate disorders: Brown-Vialetto-Van Laere syndrome and Fazio-Londe disease.
These mutations lead to the production of abnormal RFVT3 proteins that either fail to reach the cell membrane or have impaired transport function. This results in a shortage of riboflavin absorption in the small intestine and a subsequent reduction in FAD and FMN levels. While the exact mechanism is unclear, this deficiency leads to nerve problems, including:
- Hearing loss
- Muscle weakness in the face and limbs
- Breathing problems
