DWT based coding DNA watermarking for DNA copyright protection

Abstract

DNA watermarking is a technique for copyright protection and ownership authentication of DNA sequences and ensures the security of private genetic information. This paper addresses issues regarding watermarking DNA coding sequences in the frequency domain that confer mutation resistance, amino acid conservation, and security. Multimedia watermarking is designed for robustness and invisibility mainly based on frequency domain representations. However, frequency domain watermarking for a coding DNA sequence is significantly constrained because the transformation and inverse transformation must be performed while completely conserving the amino acid sequence. In this paper, we present a coding DNA watermarking method in a lifting-based discrete wavelet transform (DWT) domain that focuses on the feasibility of frequency domain watermarking for DNA sequences. Our method divides a coding DNA sequence into a number of subsequences and allocates all codons in subsequences to a numerical code using the histogram ranks of the amino acids. Our method then calculates a set of DWT coefficients for subsequences of synonymous codons and finds a subsequence among them with DWT coefficients that are optimal for embedding watermark bits. Finally, our method substitutes this sequence for a subsequence of codons. To secure the watermark, our method generates the binary watermark based on nonlinear congruential – pseudorandom number generator (NC-PRNG) and randomly selects the embeddable position in the DWT domain of the subsequence. We experimentally verified that our method ensures not only amino acid conservation and security but also resists a point mutation rate of approximately 18.5% point mutations.