Objectives: To show the morphology of the kidneys originating from St8sia1-KO and WT mice aging from 5, 15 and 30 days using the haematoxylin-eosin staining. To measure the concentration of protein in urine from KO and WT one-month-old mice. To show distribution of GM3, GM1 and GD1a gangliosides in cortex and medulla of kidneys originating from KO and WT mice aging from 5, 15 and 30 days using ganglioside antibodies. To show distribution of flotillin-1 and transferrin receptor in cortex and medulla of kidneys originating from KO and WT mice aging from 5, 15 and 30 days using flotillin-1 and transferrin receptor antibodies. To compare the distribution of flotillin-1 and transferrin receptor to distribution of GM3, GM1 and GD1a gangliosides. To determine the position of aquaporins-1 and 2 in kidneys originating from KO and WT mice aging from 5, 15 and 30 days using aquaporin-1, aquaporin-2, flotillin-1 and transferrin receptor antibodies. Study design: Matched pair study – WT animals against animals with excluded St8sia1 gene. Material and Methods: The study includes kidney tissue originating from WT and KO mice with excluded St8sia1 gene aging from 5, 15 and 30 days. Results: Haematoxylin-eosin staining did not present any morphological differences in WT and KO kidneys. Urine analysis showed that both WT and KO mice had protein in their urine samples. Immunohistochemical analysis showed that gangliosides were more present in kidneys originating from KO mice. Same analysis showed that flotillin-1 and transferrin receptor were more present in kidneys originating from WT mice and that aquaporins-1 and 2 were equally disseminated in the cortex and medulla of kidneys originating from KO and WT mice. Conclusion: A disorder in distribution of gangliosides, flotillin-1 and transferrin receptor occurred in kidneys originating from KO mice, while at the same time aquaporin-1 and 2 distribution in kidneys stayed the same.