Pedigree Charts

Pedigree charts (family trees) are specialized diagrams used in genetics and genealogy to track inheritance patterns of traits and genetic conditions across generations. Runiq provides dedicated shapes and properties that follow medical/genetics standards for pedigree notation.

Overview

Pedigree charts use specific symbols to represent:

• Gender: Males (squares), females (circles), unknown (diamonds)
• Genetic status: Affected (filled black), carrier (half-filled), normal (white)
• Vital status: Deceased (diagonal line through symbol)
• Relationships: Marriages (horizontal line, no arrow), consanguinity (double line)

Basic Shapes

Runiq provides three pedigree shapes that automatically render according to standard conventions:

Male Individual

shape father as @pedigree-male label:"Father"

Renders as a square (40×40px) with black outline.

Female Individual

shape mother as @pedigree-female label:"Mother"

Renders as a circle (38px diameter) with black outline.

Unknown Sex

shape child as @pedigree-unknown label:"Unknown"

Renders as a diamond (40×40px) with black outline.

Genetic Status Properties

Use inline properties to indicate genetic status:

Affected Individual

Black-filled symbol indicates the person has the trait/condition:

shape patient as @pedigree-male label:"Patient" affected:true

Carrier Individual

Half-filled symbol (vertical stripe pattern) indicates carrier status:

shape carrier as @pedigree-female label:"Carrier" carrier:true

Normal Individual

White-filled symbol (default) indicates no trait/condition:

shape normal as @pedigree-male label:"Normal"

Deceased Individual

Diagonal line through symbol indicates deceased:

shape grandfather as @pedigree-male label:"Grandfather" deceased:true

Relationship Notation

Marriage/Partnership

Use arrowType:none to create horizontal marriage lines without directional arrows:

husband -> wife arrowType:none

Consanguineous Marriage

Use lineStyle:double for blood-related spouses (e.g., cousins):

cousin1 -> cousin2 lineStyle:double arrowType:none

Parent-Child Relationships

Standard directed edges represent descent:

father -> child
mother -> child

Complete Example

Here's a three-generation pedigree showing autosomal recessive inheritance:

diagram "Genetic Trait Inheritance" {
  direction:TB

  # Generation I - Both carriers
  shape i1 as @pedigree-male label:"I-1" carrier:true
  shape i2 as @pedigree-female label:"I-2" carrier:true

  # Generation II - Mix of affected, carrier, and normal
  shape ii1 as @pedigree-female label:"II-1"
  shape ii2 as @pedigree-male label:"II-2" carrier:true
  shape ii3 as @pedigree-female label:"II-3" affected:true

  # Generation III
  shape iii1 as @pedigree-male label:"III-1" carrier:true

  # Marriages
  i1 -> i2 arrowType:none

  # Parent-child relationships
  i1 -> ii1
  i1 -> ii2
  i1 -> ii3
  i2 -> ii1
  i2 -> ii2
  i2 -> ii3
}

Property Reference

Node Properties

Property	Type	Values	Description
affected	boolean	true / false	Black fill - has the trait/condition
carrier	boolean	true / false	Half-fill pattern - carries one copy
deceased	boolean	true / false	Diagonal line overlay

Edge Properties

Property	Type	Values	Description
arrowType	string	none, standard, hollow, open	Arrow head style (use none for marriages)
lineStyle	string	solid, dashed, dotted, double	Line appearance (double for consanguinity)

Best Practices

Layout Direction

Always use direction:TB (top-to-bottom) for pedigree charts:

diagram "My Pedigree" {
  direction:TB
  # ... shapes and edges
}

Generation Labeling

Use Roman numerals (I, II, III) for generation labels:

shape i1 as @pedigree-male label:"I-1"
shape ii1 as @pedigree-female label:"II-1"

Node IDs

Use short, lowercase IDs without special characters:

# Good
shape i1 as @pedigree-male
shape iipartner as @pedigree-female

# Avoid
shape I-1 as @pedigree-male  # Hyphens in IDs
shape II_Partner as @pedigree-female  # Underscores

Marriage Edges First

Define marriage edges before parent-child edges for better visual clarity:

# Marriages first
grandfather -> grandmother arrowType:none
father -> mother arrowType:none

# Then parent-child
grandfather -> father
grandmother -> father

Advanced Features

Multiple Marriages

Show sequential marriages by creating separate marriage edges:

shape person as @pedigree-male label:"Person"
shape spouse1 as @pedigree-female label:"Spouse 1" deceased:true
shape spouse2 as @pedigree-female label:"Spouse 2"

person -> spouse1 arrowType:none
person -> spouse2 arrowType:none

Combining Properties

You can combine multiple properties on one individual:

shape patient as @pedigree-male label:"Patient" affected:true deceased:true

This renders a black-filled square with a diagonal line (affected and deceased).

Legend/Key

While Runiq doesn't auto-generate legends, you can add explanatory notes in comments:

# Legend:
# ■ (filled) = Affected
# ▦ (half-filled) = Carrier
# □ (empty) = Normal
# ⌿ (diagonal line) = Deceased

Medical Standards Compliance

Runiq's pedigree implementation follows these standards:

• Square = Male, Circle = Female, Diamond = Unknown sex
• Black fill = Affected by condition
• Half-fill = Carrier (heterozygous)
• White fill = Unaffected (normal)
• Diagonal line = Deceased
• Horizontal line, no arrow = Marriage/Mating
• Double line = Consanguineous marriage

These conventions are widely used in:

• Medical genetics clinics
• Genetic counseling
• Research publications
• Educational materials

Limitations

Current

• Layout is optimized for hierarchical flow, not traditional pedigree tree alignment
• Children descend directly from parents rather than from a marriage line
• Siblings may not always align perfectly on the same horizontal level

Workarounds

• Use direction:TB for best results
• Order nodes in generation groups for clearer structure
• Consider using containers with algorithm:mrtree for tree-like layout (experimental)

Examples

See the examples/pedigree/ directory for complete examples:

• simple-3-generation.runiq - Basic three-generation family
• genetic-trait.runiq - Autosomal recessive inheritance pattern
• test-consanguinity.runiq - Consanguineous marriage example
• test-marriage-edges.runiq - Marriage edge notation

See Also

• Shapes Reference - Complete shape documentation
• Edge Properties - Edge styling options
• Layout Options - Direction and algorithm settings