To determine whether we could validate these findings, we managed to collect and analyse a cohort of 185 CRC patients diagnosed with CRC before the age of 50 years originating from the Netherlands (n = 105) and Germany (n = 80), as well as a control cohort of 532 healthy individuals, for the presence of deleterious BLM mutations. The gene discussed is BLM; the disease is colorectal carcinoma.