Benedictine monastery on the Island of Rab hides the mystery of sunlight influence on development of macular degeneration (AMD). Is a harmful sunlight, risk factor or cause of macular degeneration?

Benedictine Monastery of St. Andrew is probably the oldest existing Benedictine monastery in this area. According to hundreds of years of legend, it was founded in 1018 year. In clinical examination about the possibility of the macular degeneration occurrence in 15 Benedictine sisters, we found the age-related macular degeneration (AMD) in two cases only. In 13 other sisters aging 27, 60, 67years, the fundus picture was like in a baby, vision, visual field and meridian thresholds were normal. What is the explanation for this phenomenon? Two sisters with AMD work and live as the farm workers, but the other sisters live in closed monastery with very low natural sunlight, approximately 300-500 lx. In conclusion, the earlier author's experimental and clinical works follow the consequence that without exposure of eyes to harmful higher doses of sunlight, it is not possible to develop AMD. The harmful cumulative dose of sunlight is not the risk factor but the cause, including the inheritance, for AMD development.