A molecular link which ties two rare inherited disorders - Fanconi Anemia (FA) and Bloom's Syndrome (BS)- has been found in a new study.
The study, which also explains why these diseases result in genetic instability, has appeared in the December 24th issue of the journal Molecular Cell.
FA and BS have some common key features.
Both are related to disrupted DNA repair mechanisms and high cancer risk. The genetic mutations linked to FA and BS influence large molecular complexes made up of numerous proteins (the FA and BS core complexes) that take part in important DNA repair processes.
Study author Dr. Stephen C. West from the London Research Institute said: "There is strong clinical and biochemical evidence suggesting that FA and BS proteins may act in a common DNA repair pathway.
"However, the specific interactions are poorly understood."
Dr. West and co-author, Dr. Andrew J. Deans, analysed the FA gene FANCM as it directly binds to DNA and has been known to have specificity for substrates that are alike those linked with the BS core complex.
Scientists recognized two regions in the FANCM protein that physically linked the FA core complex and the BS complex. FA and BS complexes bound independently to FANCM, but did not bind with each other when FANCM was not present.
Researchers proved that a interruption in the interaction between the two core complexes and FANCM led to almost same chromosomal repair defects representative of both BA and FA cells.
Dr West said: "We have shown for the first time that FANCM acts as a molecular scaffold that functions in a variety of repair reactions and serves as a bridge between FA and BS. The biological and clinical implications of this link are likely to be important in relation to the phenotypes associated with these genetic disorders."
"Further understanding how these interactions and reactions are regulated should provide a more complete understanding of the molecular basis of FA and BS," he added.