Today, genetic studies yield quite a large amount of information about a person, which, in many cases, allows predicting the risks of certain diseases. This gives grounds to believe that such testing can also be applied in the field of manned spaceflights in order to identify candidates best adapted to specific risks. The article examines publications on genetic polymorphisms and their effects on the carrier phenotype, namely, on such manifestations that are of interest in the context of risks arising during long-term space flights. Specific genes are listed and examples of allelic variants are given. Publications describing new molecular methods of monitoring human health are also considered, biomarkers that can be used for research in the interests of regular examination of active astronauts are identified.