Misbehaving mitochondria linked to infertility

Scientists are hopeful that a new finding will direct research related to human infertility in the right direction. — dpa

Chinese scientists believe they might have pinpointed the reason behind one of the chief causes of female infertility.

Premature ovarian insufficiency (POI), which is also called premature ovarian failure, is estimated to cause infertility in almost 4% of women.

POI is when a woman under 40 does not produce eggs regularly.

Sometimes mistakenly thought to be premature menopause, the condition and its causes have remained something of a mystery.

But according to the Tsinghua University team, who followed up observations of a family affected by infertility with tests on mice, POI appears to be linked to a malfunctioning gene.

The researchers used CRISPR to edit the Eif4enif1 gene in some mice before comparing fertility outcomes with mice that did not have the gene edited.

The genetic alteration led to a 33% fall in the number of pups per litter.

When examined under a microscope, cells from the mice whose genes were tinkered with, showed mitochondria clusters, rather than the usual, or healthy, pattern of even distribution around the cell.

Mitochondria function as “engines” in a cell, providing chemical energy for the cell to function properly.

Writing up their findings in the biology journal Development, the team said: “It seems likely that these misbehaving mitochondria are contributing to the fertility problems in these mice”, suggesting that the results could help direct research related to human infertility.

“We were actually surprised by the differences in the mitochondria,” said study co-author and Tsinghua School of Medicine professor Dr Kee Kehkoo (who is from Malaysia).

“At the time we were doing this research, a link between Eif4enif1 and mitochondria had not been seen before.” – dpa