20.8 MB (1.4 MB compressed)
3380 x 2151 pixels
28.7 x 18.3 cm ⏐ 11.3 x 7.2 in (300dpi)
PHILIPPE PLAILLY / SCIENCE PHOTO LIBRARY PHILIPPE PLAILLY / SCIENCE PHOTO LIBRARY
Human genome research: computer analysis of DNA sequencing autoradiograms, used to decode the base sequence, or chemical blueprint, of lengths of DNA. The two strands of nucleotides which form DNA are joined by base pairing; adenine (A) always pairs with thymine (T), guanine (G) with cytosine (C). Hence the progression of its bases defines a section of DNA. Decoding a sequence is done by electrophoresis through an agarose gel, where fragments of radioactively-tagged DNA separate according to size. The banding pattern is revealed under ultraviolet light. A permanent copy obtained by blotting with radiographic film, serves as input for the computer analysis.
Model release not required. Property release not required.