FSHD Region Gene 2 (FRG2)

Two potential nuclear localization signals at amino acid positions 96 and 157 were predicted as well as a peroxisomal targeting signal (PTS1) at the C-terminal end of the protein.

FRG2 expression was undetectable in all tissues tested except for differentiating myoblasts of patients with facioscapulohumeral muscular dystrophy (FSHD), which displayed low, yet distinct levels of FRG2 expression, partly from chromosome 4 but predominantly originating from its homolog on chromosome 10. However, in non-FSHD myopathy patients, only distantly related FRG2 homologs were transcribed, whereas differentiating myoblasts from healthy controls failed to express any member of this gene family. In FSHD muscle, genes located upstream of D4Z4 on 4q35, including FRG1, FRG2, and ANT1, are inappropriately overexpressed.