However, in the following example, association results across multiple tissues do not allow us to discriminate the tissue of action. C4A is a gene with strong evidence of causal effect on schizophrenia risk via excessive synaptic pruning in the brain during development32. Our results show that C4A is associated with schizophrenia risk in all tissues (p < 2.5 × 10−7 in 36 tissue models and p < 0.05 for the remaining four tissue models).
