Study of Constitutional Genetic Markers in Familial Cancer Cases

Abstract

Cancer is a multifactorial condition produced by environmental and genetic factors that drive a normal cell to turn into a malignant cell through a sequence of molecular alterations. Most malignancies are sporadic, while 15-25% are caused by inherited mutations. The incidence of the same cancer in two or more family members is the criteria to define familial cancer. A more specific description of hereditary cancer through recognised predisposing genes is a high risk of cancer in the family. The most prevalent familial cancer is prostate cancer (20.5%), breast cancer (13.58%), and colorectal cancer (12.80%). The absence of a correlation between spouses' cancer risk, especially for those not linked to tobacco use or sun exposure, shows that hereditary factors mostly bring on familial malignancies. If all the genes causing these syndromes were known and all newly diagnosed cancer patients could be tested for genetic makeup it would be rather simple to identify families with familial cancer syndromes. The deployment of widespread genetic screening would face several ethical, practical, and other obstacles even if all the genes were known. Genetic changes that impact the structure, function, and number of corresponding proteins in numerous genes and the common influence of environment and lifestyle together with the common influence of environment and lifestyle, may lead to an increased risk of cancer. Performing comprehensive exome research on non-consanguineous families with a history of several cancer cases over several generations is part of this effort. In this study, family medical histories were gathered to determine illness inheritance patterns within a family, and pedigree charts were prepared. Blood samples were taken from affected and unaffected family members with their signed informed consent. Open sources like Clingen, Clinvar, NCBI, etc. were used for data mining and bioanalysis of the collected data. The ACMG guidelines were followed for the interpretation of constitutional genetic variations. This study will help find novel genetic variants along with known variants followed by a cancer risk evaluation which will contribute to improving cancer management.