An understanding of the disorders began with the identification of (CGG)n trinucleotide repeats within the 5′ untranslated region (UTR) of FMR1 gene in Fragile X syndrome [12,13,14,15] and (CAG)n trinucleotide repeats within the coding region of the androgen receptor (AR) gene in spinobulbar muscular atrophy [16]. Here, AR is linked to fragile X syndrome.