Mutations in XPR1 cause primary familial brain calcification associated with altered phosphate export

Area of Science:

• Neurology
• Genetics
• Biochemistry

Background:

• Primary familial brain calcification (PFBC) is a rare neurological disorder.
• PFBC involves calcium phosphate deposits in brain regions like the basal ganglia.
• Previous research linked PFBC to mutations in SLC20A2, PDGFB, or PDGFRB genes.

Purpose of the Study:

• To investigate the genetic basis of PFBC in families.
• To identify novel genes associated with primary familial brain calcification.
• To understand the role of phosphate homeostasis in PFBC pathogenesis.

Main Methods:

• Genetic analysis of families affected by PFBC.
• Mutation screening in candidate genes.
• Functional analysis of identified gene variants.

Main Results:

• Mutations in the XPR1 gene were identified in multiple families with PFBC.
• XPR1 encodes a retroviral receptor involved in phosphate export.
• These XPR1 mutations were shown to alter phosphate export function.

Conclusions:

• XPR1 is a newly identified gene associated with primary familial brain calcification.
• Altered phosphate export due to XPR1 mutations contributes to PFBC.
• Phosphate homeostasis is implicated as a key factor in the development of PFBC.