br Conclusion Our study of late life depression provides evi
Conclusion Our study of late-life depression provides evidence of genotype-specific associations between depression and ACE methylation, as well as inverse correlations between ACE methylation and MHY1485 secretion. These findings highlight the potential need to consider methylation levels in combination with genetic variation in the development of effective depression biomarkers. Given this novel finding, the small effect sizes observed and the potential relationship between age and DNA methylation patterns, replication in large independent populations are needed to confirm these findings. Extending methylation analysis to cover the entire gene and associated regulatory regions, and to other potential HPA axis genes should be considered. Importantly, future investigation of the mechanisms behind the genomic control of the epigenome in ACE need to be undertaken.
Conflict of interest
Acknowledgments We thank all of the participants, and Dr Benjamin Ong for assistance with the Sequenom MassARRAY platform. The ESPRIT project is financed by the regional government of Languedoc-Roussillon, the Agence Nationale de la Recherche Project 07 LVIE 004, and an unconditional grant from Norvartis. This work was also supported by the National Health and Medical Research Council, through a Senior Research Fellowship (APP1045161 to RS); the Murdoch Children’s Research Institute (studentship to DL); the Victorian Government’s Operational Infrastructure Support Program. The funders had no role in the design and conduct of the study, in data collection, management, analysis or interpretation of the data and were not involved with the writing, preparation, review or approval of the manuscript.
Introduction Most countries allow for a deduction of debt interest in the corporate tax base, but do not allow a deduction of the opportunity cost of equity. Debt finance, therefore, is at an advantage compared to financing an investment via retained earnings or equity. This may lead to too much debt, too high risk premiums being paid, as well as moral hazard problems (see, e.g., Myers, 1977). In order to avoid such problems, the Comprehensive Business Income Tax (CBIT) and the Allowance for Corporate Equity tax (ACE) schemes have recently gained interest in European policy debates. The CBIT makes the corporation tax neutral towards the financing structure by disallowing the deduction of interest paid for corporate income tax purposes. ACE obtains the same result by granting equity holders an allowance equal to a notional return on equity (e.g., the market interest rate for long-term government bonds). Corporate tax reform under either of these two schemes has in common that they lead to neutrality between debt and equity finance, but the tax base is narrower under an ACE tax due to the allowance for equity. The literature about the effects of ACE and CBIT is scant and focuses exclusively on perfect competition, though imperfect competition is widespread in markets. This paper investigates CBIT and ACE taxation under imperfect competition using a Salop type model (within industry analysis) and a Dixit-Stiglitz type of monopolistic competition model (across industry analysis). We show that the effects of either tax system depend on industry characteristics (technology) and the intensity of competition. Under both models of imperfect competition, we find that an increase in the corporate tax rate increases production but reduces entry. Furthermore, a switch from CBIT to ACE lowers consumer prices in both models of imperfect competition. Using an oligopoly model à la Salop (1979), where firms compete in prices and sell differentiated products, we show that, with free entry, both ACE and CBIT taxations distort the market equilibrium. ACE taxation may lead to less market entry than CBIT because it induces fiercer competition. This happens under decreasing returns to scale (DRS) because the direct profit gain of capital cost deductions under ACE is more than offset by the strategic price response by firms. The reverse is true for industries with increasing returns to scale (IRS). For constant returns to scale (CRS) industries, the direct capital cost saving and the strategic price effect exactly cancel out, and the two tax regimes result in identical entry levels. We also show that irrespective of technology, equilibrium prices are always lower under ACE than CBIT.