Genetic and environmental links to fainting

Fainting has complex causes involving both genetic predisposition and environmental triggers, a new study of twins led by the University of Melbourne and Austin Health has shown. The research found that identical twins were nearly twice as likely to both faint compared to non identical twins. 'Study author Professor Sam Berkovic from the University of Melbourne based at Austin Health, said the question of whether fainting was caused by genetic factors, environmental factors or a mixture of both had been the subject of much debate.' '"This twins study has revealed that the complex causes of fainting are both genetic and environmental," he said. Fainting, also called vasovagal syncope, is a brief loss of consciousness when your body reacts to certain triggers, such as experiencing heat, pain, distress, anxiety, hyperventilating or the sight of blood. Around 25 percent of the population faint at some time in their life. While fainting is normally a very mild condition, it can cause blackouts and dizziness and can be confused with epilepsy. Berkovic said the mechanisms of fainting were poorly understood.