..............which is why the environmental risk factors are so important.
Nevetheless, GWAS have been more successful in identifying genes associated with simple traits, biochemical measures for example.
Diseases are much more complex. In Alzheimer's disease for example, cholesterol, lipoproteins, apoptosis, calcium, glutamate, acetylcholine, free radicals , cell cycle, mitochondria, the immune system, APP, tau, pathogens etc. all play a role . The efficiency of each of these mini processes is governed by genes, many of which were found pre-GWAS.
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