This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. ABSTRACT Certain genetic syndromes are known to predispose affected patients to cancer more than the general population. For some of these disorders, the genetic defect has been characterized in humans; in others, studies in yeast or animal models are providing early answers regarding the genetic basis for disease. There are still many rare inherited disorders that are far from being characterized at the genetic level. For these disorders, primary data needs to be gathered at the clinical level. Because they are rare disorders worldwide, accumulating affected patients and their relatives in order to study their genetic material becomes a difficult task. This study would allow the collection of samples from patients and their family members so that molecular and genetic studies can be conducted to better understand both the primary syndrome and the predisposition toward cancer development. HYPOTHESIS Studying rare cancer predisposition syndromes both at the clinical and molecular level will provide insight into the pathogenesis of cancer in the general population. SPECIFIC AIMS 1. Collect and alaynze clinical samples from both patients affected by a familial cancer syndrome and their family members. Familial cancer syndromes include examples such as familial colon cancer, familial breast-ovarian cancer, ataxiatelangiectasia, Bloom's syndrome, xeroderma pigmentosa, and Rothmund-Thomson Syndrome (RTS). Samples would include bood, tissues (normal and tumor) and body fluids which would be made available to investigators for the purpose of conducting research that will help to define and characterize the underlying genetic defects which cause these inherited disorders and their propensity toward cancer. 2. Collect and analyze medical records from both patients affected by a familial cancer syndrome and their family members. Clinical information will allow genotype-phenotype analyses in combination with molecular studies.