Updated by: Arabinda Naik
Pedigree analysis, also known as pedigree chart or family tree analysis, is a graphical representation and systematic study of the inheritance of traits or diseases within a family over multiple generations. It is a valuable tool in genetics and genetic counseling, allowing researchers, geneticists, and healthcare professionals to trace the transmission of genetic traits and diseases through a family's lineage. The primary objectives of pedigree analysis include:
Determining Inheritance Patterns: Pedigrees are used to identify the inheritance patterns of specific traits or diseases, such as autosomal dominant, autosomal recessive, X-linked, or mitochondrial inheritance.
Identifying Affected and Carrier Individuals: Pedigrees help in identifying individuals who exhibit the trait or disease (affected individuals) and those who carry the gene but do not show symptoms (carriers). This information is crucial for assessing the risk of inheritance and genetic counseling.
Predicting the Risk of Inheritance: By analyzing the pedigree, one can estimate the probability of future generations inheriting a specific trait or disease, which can be important for making informed decisions about family planning and medical management.
Studying the Genetic Basis of Diseases: Pedigree analysis can provide insights into the genetic basis of diseases and help identify candidate genes responsible for specific conditions.
A typical pedigree chart uses various symbols to represent family members, their relationships, and their genetic status with respect to a particular trait or disease. Common symbols used in pedigree analysis include circles (for females) and squares (for males) to represent individuals, lines to connect parents to their offspring, shading to indicate affected individuals, and half-filled symbols to represent carriers of a genetic condition. Pedigree analysis is essential in various fields, including medical genetics, animal breeding, and evolutionary biology, as it helps researchers and healthcare professionals better understand and predict genetic patterns and make informed decisions related to genetic counseling and treatment.