Blood analysis is time consuming and laboratories may require methods of storing samples until time permits analysis. The effects of storage on the sample are mostly unknown, yet some laboratories commonly store blood samples to allow processing of samples in batches. Cryopreservation is proposed as a convenient means of preserving blood samples, as the associated cold temperatures render cryopreservation an ideal storage method for tests requiring viable cells. In the literature, few studies have explored whether cryopreserved whole blood samples can be utilised effectively for cytogenetic testing. This study extended the work on cryopreservation of blood to observe the cytogenetic effects of storing whole blood samples for an extended period. In this study three cytogenetic tests: Sister Chromatid Exchange (SCE), Micronucleus Assay (MN) and Fluorescence in situ Hybridisation (FISH) were conducted on whole blood samples from ten participants to observe whether the results from the cytogenetic tests are statistically consistent over a prolonged period of cryopreservation (fresh, one month, three months and six months). These tests were conducted on a single blood sample cryopreserved from each participant. The results indicated that cryopreservation of whole blood is not a reliable method for storing blood samples prior to cytomolecular tests. The culturing of lymphocytes from cryopreserved blood was found to be inconsistent and the lymphocyte viability after cryopreservation reduced. When lymphocytes were successfully cultured, SCE and MN demonstrated increased genetic damage after a period of cryopreservation (P= <0.050 and P= 0.016 respectively) but FISH was not successfully performed on cryopreserved blood samples. It is unclear from the results obtained whether cryopreservation actually induces genetic damage or if the observed damage was the result of the specific storage technique.