both are involved in the regulation of blood pressure. 'Polydipsia' is a symptom found in more than one disease. One of these is Autosomal dominant familial neurohypophyseal diabetes insipidus (ADNDI), some times caused by a missense mutation in AVP [62]. Mutations in ACE have also been shown to be a risk factor in a different disease, schizophrenia, for which polydipsia is also symptom [63]. Thus linkage of ACE and AVP through this term is a not a consequence of their joint role in blood pressure regulation. These indirect linkages are a source of noise in the matrix, but are generally rare.
