Goldfish can make alcohol due to protein mutation

Ever wondered why your goldfish in the aquarium seems less inhibited than the other fish? A new study has revealed that goldfish produce alcohol to survive harsh winters beneath frozen lakes, which naturally makes them ‘lose their inhibition.’

The study goes on to add that humans would die with minutes without oxygen, yet the plucky little fish can survive months in oxygen-free water by converting lactic acid into ethanol. This stops them from poisoning themselves, and goes on to produce a little bit of alcohol, which perhaps makes them a tiny bit tipsy as well.

Research led by the University of Liverpool and Oslo found that the crucian carp produce 50 to 100 mg alcohol per millilitre in their blood.

Michale Berenbrink, an evolutionary physiologist at the University of Liverpool told MailOnline that this would put them above legal drink drive limit in most countries.

Researchers measured the blood alcohol limits of domestic goldfish in a lab and found they could also reach levels of around 50 mg per 100 ml.

Dr Berenbrink went on to add that putting an average sized goldfish into a pint glass and closing it off from the air would take more than 100 days to get the alcohol concentration of a typical lager.

Experiments by other researchers also showed that high alcohol levels make them less anxious.

The team has shown that muscles of goldfish and crucian carp contain not just one, but two sets of proteins normally used to channel carbohydrates towards their breakdown within a cell's mitochondria - a key step for energy production.

While one set of these proteins appears very similar to that in other species, the second set is strongly activated by the absence of oxygen.

This mutation allows them to make ethanol outside the mitochondria.

Researchers say this explains why goldfish are such resilient pets.