For example; in asymptomatic carriers of retinitis pigmentosa, a group of rare, genetic disorders that involve a breakdown and loss of cells in the retina, low level expression of CNOT3 leads to higher level of the wild-type splicing factor PRPF31 mRNA, confirming a repressive regulation by CNOT3 on PRPF31 gene expression in human cells [195,196]. This evidence concerns the gene PRPF31 and retinitis pigmentosa.