CAMBRIDGE, England, Jan. 21 (UPI) -- DNA, normally structured as
a double helix, has been seen in a "quadruple helix" form in
human cells and could be related to cancer, British researchers
say. The double helix has been considered the normal form of DNA
for 60 years, since researchers James Watson and Francis Crick
described the way two long chemical chains wound up around each
other to encode the information that cells need to build and
maintain our bodies. A four-stranded version scientists have
been able to produce in test tubes for a number of years has now
been found in human cells for the first time, the BBC reported
Monday. Researchers at Cambridge University found the four-
stranded DNA arose most frequently during a phase when a cell
copies its DNA just prior to dividing. That could be significant
in the study of cancers, they said, which are usually driven by
genes that mutate to increase DNA copying. "The existence of
these structures may be loaded when the cell has a certain
genotype or a certain