To describe the first symptom/sign and first diagnosis in patients with sporadic Creutzfeldt-Jakob disease (sCJD) in Germany with respect to M129V polymorphism of the prion protein gene and prion protein type. Data on the first symptom/sign and first diagnosis were studied in 492 sCJD patients with probable and definite sCJD and known M129V polymorphism. Unspecific prodromal symptoms such as headache, fatigue, sleep disturbances, "peculiar feeling in the head", photophobia or weight loss were found in about 10 % of the patients. No prodromal symptoms were found in MV2 and VV1 patients. Dementia was the most common first symptom (37 %) followed by cerebellar (34 %), visual (15 %), and psychiatric disturbances (14 %). The CJD diagnosis was the first diagnosis in only 35 % of the patients (in 42 % of MM, 28 % of MV, and 24.5 % of VV patients). We provide a detailed analysis on clinical presentation and first diagnosis in a large group of patients with sCJD with respect to M129V genotype and prion protein type. These data emphasize the importance of knowledge about CJD and especially rare CJD types among physicians of different specializations. Our findings may improve early recognition of atypical CJD forms.