The opinion on the usefulness of selected genetic examinations in connective tissue diseases is reported. Particular attention was paid to healing of fractures especially in respect of pathological aspects of accretion processes. The reasons for a delay in or a lack of bone fracture union process have not been fully explained--in spite of several reports relating to this type of examination. There are a number of egzogenic and endogenic agents including cytokines which regulate these processes. Up to date views on the suspected influence of cytokines on genetic polymorphism are discussed in present paper. Genetic polymorphism of some cytokines may increase the risk of post-menopausal osteoporosis. It seems that genetic factors are likely to cause complications of fracture healing.