Cell study offers clues on fertility

Congenital disorders such as Down’s syndrome could be better understood, following insights into how healthy cells form.

Scientists have identified a set of proteins that play a key role in preventing errors during the formation of healthy cells.

The results may shed light on the mechanisms involved in formation of healthy egg cells in humans, and aid understanding of how infertility, stillbirths and birth defects arise.

Yeast study

Researchers at the University of Edinburgh and the Max Planck Institute made the discovery using yeast - a model organism whose cells are very similar to those of humans.

Scientists studied processes involved in the natural re-ordering of genetic information that occurs before cell division.

This reshuffling of genes is essential in reproductive cells and occurs in most, but not all, of a cell’s packed DNA.

DNA ordering

Researchers identified a set of proteins, known as Ctf19, which help suppress this re-ordering in some parts of the DNA.

They found that this suppression process helps correctly distribute genetic material into packages known as chromosomes.

When the process misfires, it leads to abnormal re-ordering of genetic material in sections of DNA that normally aid cell division.

This same error in DNA distribution in humans causes egg cells to have the wrong number of chromosomes - known as aneuploidy - and leads to common congenital conditions.

Coloured markers

Researchers used fluorescent markers to highlight how genetic material moved during cell division in yeast.

They found that when the protein was absent, the cell division was more likely to be flawed.

They corroborated their findings by analysing the genes of newly formed cells.

Their study, published in eLife, was supported by the Wellcome Trust.