Making advances in disease prevention

Specialists from Renji Hospital have developed a strategy for preventing and correcting maternally transmitted nongenetic diseases or disorders, and will also facilitate the investigation of maternally transmitted nongenetic information at the very beginning of life.

Mammalian oocytes carry specific nongenetic information, including DNA methylation to the next generation, which is a factor in development and disease.

Many mammalian nongenetic diseases and developmental disorders originate from oocyte DNA methylation abnormalities because of the environment, the mother’s psychological trauma or other reasons and inherited by the children, who can suffer over growth, slow growth, intelligence disability or other abnormalities.

“Take autism for example, only 5 percent of children are found with genetic changes while the rest 95 percent have normal genes. So we suspect that their problems are related with oocyte DNA methylation abnormalities,” said Dr Sun Yun from Renji Hospital’s reproductive medicine department.

However, prevention and correction of this maternally transmitted nongenetic disorder remains challenging because of the lack of a strategy that can evaluate and manipulate specific methylation at single oocyte level, she said.

In the research, specialists use mice.

“By using several models of epigenetic inheritance via oocytes, we have shown that specific methylation in a single oocyte can be evaluated from its sibling first polar body and can be edited in a targeted manner,” Sun said.

The article was published by the Proceedings of the National Academy of Sciences of the United States of America, or PNAS.