The science of blindness

Which sense do you value the most? I think many people, if they had to choose, would stick to their vision as the must-have sense. One thing that I want to get beyond on this blog is the tendency to find the one-gene-that-causes-all phenomenon. This tendency to fix on genes of large and singular affect, traditional Mendelian phenotypes like cystic fibrosis (a recessive disease), has been dictated by the lack of power of and limitations in studying quantitative traits, where I think the real uncharted territory is going to be with the next few decades. Nevertheless, a new paper in Nature Genetics caught my eye, so to speak. The authors suggest that "...analysis of the C2 and BF haplotypes and CFH variants shows that variation in the two loci can predict the clinical outcome in 74% of the affected individuals and 56% of the controls." In short, the most common form of blindness in the modern world can be predicted to a large extent by two loci. This is a step beyond the one-gene-gene-that-causes-all narrative, as you have to take into account two locations on the genome, but it shows that relatively simple traits of interest are still around as "low hanging fruit."