CLCN7 and osteopetrosis: Additionally, Steven et al. have estimated the penetrance of ADO II to be approximately 66% (62 clinically affected individuals/94 subjects with the gene mutation), which means among the individuals with CLCN7 mutations, one third were asymptomatic gene carriers without osteopetrosis-related signs in clinical, biochemical, and radiological results (Waguespack et al., 2003).