TEMPLATE
Blank Pedigree Chart
Start with an empty analysis canvas and add people with the People toolbox or the Quick Add menu. The chart starts with a single generic trait named “Trait of interest” so you can define your own shading later. Use Auto Layout whenever you want a tidy generation-by-generation arrangement.
Inheritance pattern & biological mechanism
A clean, unconstrained canvas designed for clinical consultations, classroom problem-solving, and genealogical health charting. Starting without pre-configured people or traits provides total flexibility to establish the proband, assemble nuclear and extended families, and define customized disease or carrier phenotypes as information is collected.
Key transmission rules
- Standard pedigree layout positions older generations at the top (Generation I) and succeeding generations downward (II, III, IV).
- Biological parents are connected by a horizontal union line; a vertical descent line drops to a horizontal sibling line connecting children in birth order (oldest on the left).
- Square symbols designate males, circular symbols designate females, and diamond symbols designate individuals whose sex is unknown, undocumented, or undisclosed.
- Shading indicates phenotypic expression of the trait or disorder of interest, with carrier status shown by a central dot or half-shading.
Representative real-world conditions
Multi-factorial Conditions
Cardiovascular disease, Type 2 diabetes
Conditions shaped by multiple interacting genetic alleles and environmental triggers across several generations.
Unknown or Suspected Inherited Syndromes
Undiagnosed family clusters
Used during initial genetics triage to document all reported symptoms before genetic testing.
How to analyze this chart
- 1
Begin by establishing the proband (the individual through whom the family came to medical attention), designated by an arrow pointing to their symbol and an uppercase letter P.
- 2
Construct the proband’s immediate sibship in chronological birth order from left to right.
- 3
Trace maternal and paternal lineages upward into parents, aunts, uncles, and grandparents, recording health status, age, and causes of death.
- 4
Apply custom traits in the editor legend to color-code multiple diagnoses across the extended pedigree.
Diagnostic checklist: confirming vs ruling out
Confirming clues
- ✓ At least three generations documented to reveal multi-generational inheritance patterns.
- ✓ Inclusion of maternal and paternal sides to verify lineage-specific segregation.
- ✓ Explicit recording of unaffected individuals to establish accurate inheritance denominators.
Caveats & ruling out
- ⚠ Beware of assuming an isolated case is non-genetic; recessive traits and de novo mutations frequently appear with clean family histories.
- ⚠ Avoid omitting deceased ancestors or pregnancy losses, as they frequently carry critical phenotypic clues.
Frequently asked questions
How many generations should I include when starting from scratch?
Clinical geneticists recommend documenting at least three generations: the patient (proband), their siblings and children, their parents, aunts, and uncles, and both sets of grandparents.
Can I add multiple medical conditions to the same blank chart?
Yes. The editor allows you to add multiple traits with distinct color assignments, enabling you to track overlapping conditions like breast cancer and ovarian cancer on the same diagram.
How do I designate a person who is deceased on the chart?
Select the individual and mark their life status as deceased in the inspector panel. The editor automatically applies the standard diagonal slash through their symbol.