Wondering why you're overly tetchy with the kids all the time? You could have an 'angry mum' gene, which makes some mothers shout at their children – especially during financially-difficult times. (Personally, I have The Angry House Dad Gene, no matter how much money I've got in my pocket, but I digress...).
According to scientists at New York University, women who carry a variant of a specific protein are predisposed to hitting or shouting at children during an economic downturn.
Scientists discovered 'harsh parenting' increased during the recession in the US. between 2007 and 2009, particularly amongst women with the so-called 'sensitive' mutation of a gene that regulates moods.
Dr Dohoon Lee, of New York University, said: "It's commonly thought economic hardship within families leads to stress which - in turn - leads to deterioration of parenting quality.
"But these findings show an economic downturn in the larger community can adversely affect parenting - regardless of the conditions individual families face."
The study, published in proceedings of the National Academy of Sciences, said the effect is only found in mothers who carry the gene version that makes them more likely to react to their environment.
Professor Irwin Garfinkel, of Columbia University, said: "This finding provides further evidence in favour of the orchid-dandelion hypothesis that humans with sensitive genes - like orchids - wilt or die in poor environments but flourish in rich environments whereas dandelions survive in poor and rich environments."
Got that? No, me neither!
More on Parentdish: Shouting
Surviving Teenagers: How to stop shouting