Primary osteoarthritis of the hip: a genetic disease caused by European genetic variants.

Primary osteoarthritis of the hip is a separate phenotype that occurs at a rate of 3% to 6% in the populations of the world with European ancestry. In all non-European populations, there is a consistent rarity of primary osteoarthritis that suggests a different etiology for these few patients. Family, sibling, and twin studies prove primary osteoarthritis to be a genetic disease with a 50% heritability caused by European genetic variants.

Primary osteoarthritis of the hip in monozygotic and dizygotic male twins.

Population and total hip replacement surveys show that primary osteoarthritis of the hip is uncommon in African Americans and rare in Asians, suggesting a genetic basis for this disease. We studied genetic influences on primary osteoarthritis of the hip by estimating monozygotic (MZ) and dizygotic (DZ) twin correlations using a two-stage data collection. A total of 6419 male veteran twins of the NAS-NRC Twin Registry, born between 1917 and 1927, were contacted by telephone (first stage).