Genetic material should be routinely collected in clinical vaccine trials--high consent rates can be achieved across all age groups.

•Genetic studies are key to understand vaccine-induced immunity and reactogenicity.•The feasibility of obtaining genetic consent in vaccine trials is currently unknown.•We assessed DNA consent rates in 11 studies involving almost 3000 participants.•Consent rates were very high across various age groups.•We propose to routinely collect genetic material in clinical vaccine trials.