[CpG island methylation patterns and expressions of H19 gene in cloned fetus of goat].

The aberrant epigenetic reprogramme is an important cause for abnormal development of nuclear transfer embryos. The objective of this study was to investigate the CpG island methylation profiles and relative expression levels of H19 gene in different tissues of cloned goat fetus. We detected liver, placenta, kidney, lung and heart in the dead cloned goat fetus and the age-matched normal goat fetus (control) by using bisulfite sequencing and real time PCR. Results indicated that methylation levels of the fifth CpG island of H19 gene in dead cloned goat fetus was significant high compared with that in the control in placenta (70% vs 49.41%, P < 0.05), and relative expression levels of H19 gene was significant low compared with that in the control (883.3 vs 1 264.5, P < 0.05). Reversely, the methylation levels was significant low compared with that in the control in lung (63.53% vs 88.24%, P < 0.05), and relative expression levels was significant high compared with that in the control (1 003.4 vs 515.5, P < 0.05). The differences of others groups were insignificant (P > 0.05). Results showed the abnormal DNA methylation proflies of H19 gene occurred in some tissues of cloned goat fetus, which affected normal expression levels of H19 gene, indicating that aberrant DNA methylation reprogramme may be one of the important factors for the death of cloned animals.