Rothmund-Thomson Syndrome

NOTE: This is a research study and is not meant to be a substitute for clinical genetic testing. Families may never receive results from the study or may receive results many years from the time they enroll. If you are interested in clinical testing please consider seeing a local genetic counselor or other genetics professional. If you have already had clinical genetic testing and meet eligibility criteria for this study as shown in the Eligibility Section, you may enroll regardless of the results of your clinical genetic testing.
While it is well recognized that hereditary factors contribute to the development of a subset of human cancers, the cause for many cancers remains unknown. The application of next generation sequencing (NGS) technologies has expanded knowledge in the field of hereditary cancer predisposition. Currently, more than 100 cancer predisposing genes have been identified, and it is now estimated that approximately 10% of all cancer patients have an underlying genetic predisposition.
The purpose of this protocol is to identify novel cancer predisposing genes and/or genetic variants. For this study, the investigators will establish a Data Registry linked to a Repository of biological samples. Health information, blood samples and occasionally leftover tumor samples will be collected from individuals with familial cancer. The investigators will use NGS approaches to find changes in genes that may be important in the development of familial cancer. The information gained from this study may provide new and better ways to diagnose and care for people with hereditary cancer.
PRIMARY OBJECTIVE:
* Establish a registry of families with clustering of cancer in which clinical data are linked to a repository of cryopreserved blood cells, germline DNA, and tumor tissues from the proband and other family members.
SECONDARY OBJECTIVE:
* Identify novel cancer predisposing genes and/or genetic variants in families with clustering of cancer for which the underlying genetic basis is unknown.

In the context of this study, the investigators wish to take advantage of high-throughput genetic techniques (microarray and high-throughput exome sequencing) to identify new genes implicated in syndromic poikiloderma so as to improve the diagnostic decision tree in these syndromes, opportunities for genetic counselling for patients and their families and the follow-up of patients, notably with regard to the risk of tumours.
This study will make it possible to identify new genes implicated in syndromic poikiloderma and improve the diagnostic strategy proposed to patients with these syndromes, and to propose to patients a confirmed diagnosis, appropriate follow-up, notably with regard to the risk of tumours, genetic counselling to families and eventually an antenatal diagnosis to couples who would like to have one for future pregnancies.
The identification of new genetic causes of syndromic poikiloderma will also make it possible to complete the current classification of these syndromes

Osteosarcoma is the most common malignant bone tumor in children and adolescents. Because cure rates for osteosarcoma have remained stagnant for the past several decades despite numerous trials of chemotherapy agents, novel therapies based on the understanding of the molecular pathogenesis of osteosarcoma are needed. Rothmund-Thomson Syndrome (RTS) is a genetic disorder affecting many parts of the body and resulting in major skeletal abnormalities. This disease also has the propensity to increase the risk of developing cancer, particularly osteosarcoma. Two-thirds of RTS patients have a high risk of developing osteosarcoma. Therefore, it is important to understand the impact of RTS on the skeletal phenotype (as measured by bone density) in order to develop effective therapies to battle osteosarcoma.