H et al (2010) reported presence of three paternally methylated DMRs (DMR1, DMR2 and DMR3) 5.0,
3.0 and 4.2 kb in length respectively) between Gpr1-Zdbf2 domain.
These DMRs were methylated from mature sperm and unmethylated in metaphase II (MII) oocytes DNA and
differentially methylated in blastocysts DNA from B6/JF1 mice. Methylation analysis of somatic
tissues from B6/JF1 and JF1/B6 embryos at E13.5 and adults showed that all the tissues (liver, lung,
heart, kidney, spleen and brain) were differentially methylated.
Although present in the germline, these DMRs appear to be re-established after implantation and
therefore might be regarded as secondary DMRs (Kobayashi H et al, 2012).