Name two error-correcting approaches used in DNA data storage.

• A. Huffman coding and Run-length encoding.
• B. Parity checks only.
• C. Turbo codes.
• D. Reed-Solomon codes and LDPC codes (often plus fountain codes in advanced schemes).

Answer: (D)

In DNA data storage, the main idea is protecting data from errors that arise during synthesis and sequencing, as well as missing pieces when some DNA strands aren’t recovered. Reed-Solomon codes are block-based error-correcting codes that add parity information across groups of data strands, which lets you recover entire missing or heavily corrupted strands. They’re especially good at correcting erasures (lost strands) and a bounded number of symbol errors, making data recovery reliable even when some pieces are damaged or lost.

LDPC codes use sparse parity-check structures and iterative decoding to correct many small errors across long sequences with high efficiency. They handle the everyday substitutions and misreads you see in sequencing quite well, providing strong error resilience with relatively low redundancy.

In practice, DNA storage schemes often layer these approaches, using Reed-Solomon as an outer code to protect against strand dropouts and LDPC as an inner code to clean up residual base-level errors. In more advanced designs, fountain codes are added to create a rateless set of strands, so data can be recovered even if only a subset of the total strands is retrieved. The combination of RS and LDPC (often with fountain codes) is well established for robust DNA data storage. The other options are not aligned with this purpose: compression schemes like Huffman or Run-length encoding don’t provide error correction; simple parity checks offer only minimal correction; Turbo codes exist but RS and LDPC are the standard, widely used choices in this context.