Second, the naturally occurring Komeda miniature rat Ishikawa mutant, which has general longitudinal growth retardation, results from a deletion in the rat gene encoding cGKII30. Therefore, in rodents, it is clear that cGKII has a role in skeletal growth, acting as a molecular switch between chondrocyte proliferation and differentiation. We predict that larger replication studies will demonstrate that common genetic variation at the PRKG2 locus does contribute to height variation in humans, but it seems possible that there will also be heterogeneity among studies.
