Offspring could inherit father’s Toxo infection

Offspring could inherit father’s Toxo infection

Illuminate newsletter index page, June 2020
June 2020

Associate Professor Chris Tonkin
Associate Professor Chris Tonkin co-led the study that
males infected with a common parasite can impact their
offspring's mental health.

Melbourne researchers have revealed that males infected with the common Toxoplasma parasite can impact their offspring’s brain health and behaviour.

Studying mice infected with Toxoplasma, the team discovered that sperm of infected fathers carried an altered ‘epigenetic’ signature that impacted the brains of resulting offspring.

The research was led by Institute researchers Dr Shiraz Tyebji and Associate Professor Chris Tonkin, in collaboration with Professor Anthony Hannan at the Florey Institute of Neuroscience and Mental Health.

Infectious inheritance

Toxoplasma is one of the world’s most common parasites, estimated to be carried by between 25 and 80 per cent of the global population.

By studying male mice infected with Toxoplasma, the researchers were able to narrow their investigations down to the transmission of epigenetic information through sperm, Dr Tyebji said.

“We discovered that Toxoplasma infection alters levels of DNA-like molecules, called small RNA, that are carried by sperm,” he said.

“These changes in small RNA levels affect gene expression, and so could potentially influence brain development and behaviour of offspring.

“We were stunned to see that even the ‘grandchildren’ of the original infected male displayed changes in their behaviour,” Dr Tyebji said.

Impacts for public health

Professor Hannan said this was the first time it had been shown that an infection in a male can result in epigenetic changes being transmitted to subsequent generations.

“We normally think more about how infectious diseases in women affect the developing fetus, but perhaps certain infections in men could have long-term impacts on subsequent generations’ health."

Super Content: 

It’s thought that an infection in humans caused by the parasite Toxoplasma gondii could cause a change in our behaviour—even a change in our personality that could 'make us' like cats.

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