KLRC2 and cytomegalovirus infection: For instance, in a study conducted in a Gambian population with a high frequency of HCMV (Human Cytomegalovirus) infection, it was reported that the percentage of terminally differentiated CD56dim CD57+NKG2C+ NK cells in young children population, were near to 70% at the age of six, which is higher than the median of the frequency of this fully mature phenotype reported in European population which is around 50%17.