Internet of Things is playing a major role by connecting everything via Internet to the Cloud. Data from things are collected at gateways and processed at the application servers. The processed data is sanitized and masked to preserve it on Cloud. The security and privacy issues such as data misuse, loss or theft make IoT Cloud more untrusted. While providing numerous benefits IoT Cloud help the business organizations grow by limiting the time and economy. Fixing the security and privacy issues would enhance the use of these technologies. This work is aimed at proposing a novel DNA based algorithm to enhance the security and privacy of data on cloud. The detailed study is conducted on the existing security schemes. Finally, clear picture on the pits and holes in existing IoT Cloud based security schemes have been presented. The proposed scheme has been tested by implementing it using opensource tools. Results generated depicts the level of security and privacy provided by the proposed scheme. This would also help researchers to analyse the efficiency of existing hybrid security schemes.