This chapter contains sections titled:

• Introduction

• Genetic Variability

• How to Detect Genetic Variability

• What to Analyze

• Environmental Factors

• Gene–Environment Interactions: Focus on Diet

• Common Genetic Variants and Gene–Diet Interactions Modulating Plasma Lipoprotein Concentrations

• Gene–Microorganisms Interactions

• The Microbiome (Microbiota)

• Conclusion

• Acknowledgments

• References