The protein encoded by this gene is a nuclear phosphoprotein of unknown function. This gene contains a tandem CGG repeat region within a CpG island that normally consists of 8-14 repeats but can expand to over 200 repeats. The repeat region is within the 5' UTR of some transcript variants, but is intronic to another variant. The expanded repeat allele is a fragile site and becomes hypermethylated, causing a reduction in gene expression. A disease phenotype has not been associated with expanded alleles. This gene is found within the rare FRA10A folate-sensitive fragile site. [provided by RefSeq, Dec 2016].