Fetal genome sequencing looking for genetic diseases can now use genetic material circulating in the mother’s blood, without the need for knowledge of the father’s genes. Scientists were able to apply a chromosome counting technique to identify the individual parental chromosomes transmitted to the fetus without any paternal information, unlike other techniques that are also more invasive and pose some risk to the fetus and mother (Nature 2012, doi:10.1038/nature11251).

Patellar fractures can occur spontaneously after the resurfacing that is part of total knee replacement surgery. A case-control study designed to identify which patients might be at increased risk of fractures identified age over 70 years at the time of surgery as a common risk factor. Patella fracture was also strongly associated with the number of previous knee operations, greater mechanical misalignment before surgery, shorter patellar tendon length after surgery, and a thinner patellar thickness after resection (Journal of Bone and Joint Surgery 2012;94B:908-13, doi:10.1302/0301-620X.94B7.28552).

There is no association between the presence of risk factors for prostate cancer and whether men think they are at risk. An analysis of men …