Age-related macular degeneration (AMD) is a leading cause of global blindness and vision impairment (Pascolini and Mariotti 2012). In the UK nearly 60% of cases of registered sight impairment and severe sight impairment are attributable to AMD (Bunce et al. 2010). Similarly, in Australia, the synthesis of data from the Melbourne Visual Impairment Project and the Blue Mountains Eye Study indicates that AMD is responsible for almost half of all cases of ‘blindness’ (Taylor et al. 2005). Around 600 000 people in the UK have AMD, a figure that is expected to rise to around 750 000 by 2020 (Minassian et al. 2011).