Among ionic channels, those that are potassium selective are, by far, the most diverse group. They play a key role in processes such as immune response, cell differentiation, excitability and cell death, among others. More than 60 genes for potassium channels are known in the human genome, which together with the fact that up to four different subunits can combine to form a channel, means that there are a large number of variants. Despite this impressive redundancy in “potassium permeation”, mutations in some subunits cause hereditary diseases, indicating that the rest of the channels cannot substitute for them. These diseases are known as channelopathies. To date, around 10 potassium channelopathies have been identified and four of these are due to mutations in genes of the KCNQ family, the gene products of which are Kv7.1-Kv7.5. Our research is focused on the molecular study of these proteins that regulate cell excitability.