Moreover, considering particular genes, deletions decreased their expression resulting in disease phenotypes, e.g., retinitis pigmentosa (deletion of an intron of the PRPF31 gene) (Ruberto et al. 2021), DiGeorge syndrome (deletions within several genes) (Sellier et al. 2014), or Fanconi anaemia (deletion in exons of the FANCA gene) (Tischkowitz et al. 2004). The gene discussed is PRPF31; the disease is 22q11.2 deletion syndrome.