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It is extremely rare, as only 33 cases have been reported in 3 families.

The disease typically has onset in late childhood or adolescence. Clinical signs include chronic bone pain and disorders of the cranial nerves (trigeminal neuralgia, facial palsy, hearing loss). The risk of fracture is not increased and patients show normal or even increased trabecular bone strength. Twenty to forty percent of cases are asymptomatic.

The disease is due to a gain-of-function mutation in the LRP5 gene (Low density lipoprotein receptor-related protein 5; 11q12-q13) which results in increased bone formation. Therefore, controversy exists whether Autosomal dominant osteopetrosis type 1 is truly a type of osteopetrosis (which is due to failure of osteoclast development or function) or whether it is more accurately described as a `high bone mass' disease.

Diagnosis is based on clinical and radiographic evaluation. Radiographs show diffuse skeletal sclerosis, with marked thickening of the cranial vault, slight sclerosis of the spine with dense vertebral arches, and thickened long bone cortices. Bone mineral density (lumbar spine, femoral neck) has a Z-score ranging from +4 to +8 SD.

Transmission is autosomal dominant. Each child of an affected individual has a 50% risk of being affected. Autosomal dominant osteopetrosis type 1 is a fully penetrant disease.

Treatment is symptomatic.

Life expectancy is normal.