The recessive disease Friedreich's ataxia is caused by a trinucleotide repeat in intron 1 of the FXN gene. Studies have shown the expansion causes decreased FXN expression, leading to the disease phenotype. Scientists have proposed several models of how the mutant locus might silenced. Which of the following is the least likely to cause silencing of the mutant FXN locus? Group of answer choices CpG methylation Histone acetyltransferase acetylating histones near the locus Mis-splicing of the FXN mRNA.