At the heart of these research areas are efforts to understand specific chemical modifications to proteins that surround DNA in its native cellular environment. These 'epigenetic marks' are indicative of gene activity ('off' versus 'on'), and can be used to understand processes underlying normal development, cellular reprogramming, and even events leading to cancer and other disease states.

One of the protocols, freely available, describes how to characterize these epigenetic marks in native chromatin (i.e., the DNA is still bound to its associated proteins, as it would exist in its normal cellular environment). It specifies how to harvest native chromatin from a variety of cell types, fractionate the chromatin into manageable fragments, and then use an antibody to tag and isolate the proteins that possess specific epigenetic marks. Because the proteins remain bound to the DNA, the researchers can determine which genes (and other genomic elements) were 'off' or 'on' in the cell.

The June release of Cold Spring Harbor Protocols also features a set of methods to investigate embryogenesis in the frog, Xenopus laevis. Xenopus are commonly used for developmental studies because they produce large embryos that develop rapidly, are easy to maintain and manipulate, and can be induced to ovulate year-round.

One of the Xenopus -related protocols describes a method for surgically isolating and culturing a specific slice of tissue from Xenopus embryos. These tissue slices, called - Keller explants,- contain cells that undergo dynamic movements and interactions during embryogenesis. The slices allow scientists to observe and test morphological and molecular changes that occur in a normally opaque embryo, and to see what?s happening several layers deep into the embryo. The protocol is freely available at cshprotocols/cgi/content/full/2007/12/pdb.prot4749.

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On the other hand, the research shows that the mutations do not totally eliminate the FANCD2 gene function, but cause a low level of expression of the FANCD2 protein. These results indicate that in humans, as opposed to what was observed in mice, the total absence of the FANCD2 protein is impossible (without this protein the embryo will not develop), and underline the findings that animal models do not always reflect the clinical phenotype of the disease.

A consortium of 13 European and North American laboratories and hospitals performed the research, which included the group directed by Dr. Jordi Surrall's of the Departament de Gen'tica i de Microbiologia (Department of Genetics and Microbiology) of the UAB and assigned to the Centro de Investigaciones Biom'dicas en Red de Enfermedades Raras del Instituto de Salud Carlos III (CIBER-ER) (Biomedical Research Centre for Rare Diseases of the Carlos III Health Institute network). The American Journal of Human Genetics published the results in their May edition.

This study, together with others published by Dr. Surrall's, team complements a model study described in the May edition of the review Cell Cycle that relates the genetic base of the disease with its clinical heterogeneous progression. This model is based on the fact that the patients with a total absence of FANCA protein, whose main function is to activate FANCD2 protein, have a milder clinical phenotype than FANCD2 patients. In turn, these are milder than patients with FANCD1/BRCA2, a gene that acts directly on a DNA level and promotes repairs in cases of genetic mutations.

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