Deoxyribonucleic acid, sodium salt, ex salmon testes

Deoxyribonucleic acid (DNA) is a long double-helical molecule containing genetic information. DNA is a double-stranded (ds) molecule. Each strand is composed of an ordered combination of four nucleotides, each nucleotide consisting of a purine or pyrimidine base (adenine, guanine, thymine, or cytosine) and linked by phosphodiester bonds. Sperm cells from salmon testes are a good source for non-mammalian DNA. It is used as blocking agent to reduce the background in nucleic acid hybridization techniques.