Family relationships and trait transmission can be drawn at a glance. A pedigree is a standardized diagram that records the inheritance of a trait or disorder across multiple generations. Squares represent males, circles females; shaded symbols indicate affected individuals.

Horizontal lines connect partners; vertical lines lead to offspring. Generations are numbered with Roman numerals, individuals with Arabic numerals. Patterns visible in the pedigree—vertical transmission, skipped generations, sex bias—suggest dominant, recessive, or sex-linked inheritance.

Genetic counselors and clinicians construct pedigrees to assess risk, guide testing, and explain inheritance to families. Accurate information from relatives is essential. Modern software assists drawing and analysis, yet the underlying logic remains the same as the hand-drawn charts of early geneticists.

• Diagram of trait inheritance across generations
• Uses standard symbols for sex and phenotype
• Reveals inheritance patterns
• Essential tool in genetic counseling