Discordance

Discordance: 1. The presence of any given condition such as HIV in only one member of a couple. 2. In genetics, the presence of a phenotype such as asthma in only one members of a twin pair. 3. In clinical care, lack of agreement between physician and patient.
In all sense, disconcordance is as opposed to concordance. From dis- + the Latin concordare, to agree = not to agree.