Notwithstanding efforts to promote early HIV testing, 20 to 40% of patients entering in care for HIV in Western Countries present with advanced HIV disease, i.e. with a CD4+ count below 200 cells/μL.[20–24] Failure to restore CD4+ count above this threshold, despite virological effective HAART, is a relatively common finding, which has been associated with increased risk of AIDS progression and death.[4,5,9,12] Whether a lack of short-term CD4+ increase, despite suppression of HIV replication, is also associated with a greater risk of non AIDS-related morbidities is still unclear. The gene discussed is CD4; the disease is AIDS.