DNA Folding Defects and Limb Malformation: It’s Not Just About DNA Sequences
How does/can a product “cause” an undesired outcome in the formation of limbs or diseases such as cancer, and how can/does one test to try to better assess opportunities and risks related to products that may have cellular level impacts? One older line answer involved the Ames test, and others, which are mainly about mutations to DNA sequences. The Ames test dates back to 1970s science.
For persons concerned about risks and opportunities related to products with cellular impacts, it’s useful to recognize the reality of the ongoing molecular biology revolution and more recent discoveries and ongoing inquiries. A cogent example of new molecular science is illustrated by a family with a “curse” of webbed fingers in some of its members, as described in a January 9, 2017 NYT article. The big picture point is that defects in folding of DNA appear to “cause” undesirable conditions and cancers. One of the related medical articles is in Nature and is open access.
Set out below is part of the text from the NYT article on the family with webbed fingers:
“The family, under promise of anonymity, is taking part in a study by Dr. Mundlos and his colleagues of the origin and development of limb malformations. And while the researchers cannot yet offer a way to prevent syndactyly, or to entirely correct it through surgery, Dr. Mundlos has sought to replace the notion of a family curse with “a rational answer for their condition,” he said — and maybe a touch of pioneers’ pride.
The scientists have traced the family’s limb anomaly to a novel class of genetic defects unlike any seen before, a finding with profound implications for understanding a raft of heretofore mysterious diseases.
The mutations affect a newly discovered design feature of the DNA molecule called topologically associating domains, or TADs. It turns out that the vast informational expanse of the genome is divvied up into a series of manageable, parochial and law-abiding neighborhoods with strict nucleic partitions between them — each one a TAD.”