The effect of the 7R allele at the DRD4 locus on risk tolerance is independent of background risk in Senegalese fishermen.

It has been shown that living in risky environments, as well as having a risky occupation, can moderate risk-tolerance. Despite the involvement of dopamine in the expectation of reward described by neurobiologists, a GWAS study was not able to demonstrate a genetic contribution of genes involved in the dopaminergic pathway in risk attitudes and gene candidate studies gave contrasting results. We test the possibility that a genetic effect of the DRD4-7R allele in risk-taking behavior could be modulated by environmental factors. We show that the increase in risk-tolerance due to the 7R allele is independent of the environmental risk in two populations in Northern Senegal, one of which is exposed to a very high risk due to dangerous fishing.

Social capital and access to primary health care in developing countries: Evidence from Sub-Saharan Africa.

We test for a causal role of social capital, as measured by self-reported trust, in determining access to basic health facilities in Sub-Saharan Africa. To skirt the reverse-causality problems between social capital and basic health, we rely on instrumental-variable (IV) estimates. A one standard-deviation increase in trust is predicted to lead to a 0.22 standard-deviation fall in doctor absenteeism, a 0.31 standard-deviation fall in waiting time and a 0.30 standard-deviation fall in bribes. As a robustness check, we also use a different database regarding a different health issue, access to clean water. We find that a one standard-deviation rise in trust leads to a 0.33 standard-deviation rise in access to clean water. The variety of public goods considered provides insights about the possible channels through which social capital is converted into health improvements.