On the other side, ZFN-inactivation of tet2, a gene coding for one of the TET family members of DNA methylcytosine oxidases that converts 5-methylcytosine into 5-hydroxymethylcitosine during the DNA demethylation process, is responsible for generalized myelodysplastic syndromes (MDS) in zebrafish [77]. Here, TET2 is linked to myelodysplastic syndrome.