Pedigree Chart Examples

Medical and genetic family trees using standard pedigree notation.

Simple Three-Generation Pedigree

A basic three-generation family tree showing affected individuals and carriers:

diagram "Simple Pedigree" {
  direction:TB

  # Generation I (Grandparents)
  shape grandfather as @pedigree-male label:"Grandfather"
  shape grandmother as @pedigree-female label:"Grandmother"

  # Generation II (Parents)
  shape father as @pedigree-male label:"Father" affected:true
  shape mother as @pedigree-female label:"Mother"
  shape uncle as @pedigree-male label:"Uncle" deceased:true

  # Generation III (Children)
  shape son1 as @pedigree-male label:"Son 1" affected:true
  shape son2 as @pedigree-male label:"Son 2"
  shape daughter as @pedigree-female label:"Daughter" carrier:true

  # Marriages (no arrows)
  grandfather -> grandmother arrowType:none
  father -> mother arrowType:none

  # Parent-child connections
  grandfather -> father
  grandfather -> uncle
  grandmother -> father
  grandmother -> uncle

  father -> son1
  father -> son2
  father -> daughter
  mother -> son1
  mother -> son2
  mother -> daughter
}

Key Features:

• ■ Black fill = Affected by condition (Father, Son 1)
• ▦ Half-fill = Carrier status (Daughter)
• ⌿ Diagonal line = Deceased (Uncle)
• Horizontal lines without arrows = Marriages

Autosomal Recessive Inheritance

Demonstrating a classic autosomal recessive pattern where both parents are carriers:

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
  shape ii4 as @pedigree-male label:"II-4" carrier:true
  shape ii5 as @pedigree-female label:"II-5"

  # Generation III
  shape iipartner as @pedigree-female label:"II-partner"
  shape iii1 as @pedigree-male label:"III-1" carrier:true
  shape iii2 as @pedigree-female label:"III-2"

  # Marriages
  i1 -> i2 arrowType:none
  ii2 -> iipartner arrowType:none

  # Parent-child (Generation I -> II)
  i1 -> ii1
  i1 -> ii2
  i1 -> ii3
  i1 -> ii4
  i1 -> ii5
  i2 -> ii1
  i2 -> ii2
  i2 -> ii3
  i2 -> ii4
  i2 -> ii5

  # Parent-child (Generation II -> III)
  ii2 -> iii1
  ii2 -> iii2
  iipartner -> iii1
  iipartner -> iii2
}

Expected Ratio: With two carrier parents (I-1 × I-2):

• 25% affected (II-3)
• 50% carriers (II-2, II-4)
• 25% normal (II-1, II-5)

Consanguineous Marriage

Showing blood-related spouses (e.g., cousins) using double line notation:

diagram "Consanguinity" {
  direction:TB

  # Cousins who marry
  shape cousin1 as @pedigree-male label:"Cousin 1"
  shape cousin2 as @pedigree-female label:"Cousin 2"

  # Child
  shape child as @pedigree-male label:"Child" affected:true

  # Consanguineous marriage (double line, no arrow)
  cousin1 -> cousin2 lineStyle:double arrowType:none

  # Parent-child
  cousin1 -> child
  cousin2 -> child
}

Double Line Notation: The lineStyle:double property creates parallel lines 6px apart, the standard symbol for consanguineous (blood-related) marriages. This is important in genetics for tracking increased risk of recessive conditions.

Multiple Marriages

Tracking sequential marriages and half-siblings:

diagram "Multiple Marriages" {
  direction:TB

  # Person with two marriages
  shape person as @pedigree-male label:"Father"
  shape spouse1 as @pedigree-female label:"Wife 1" deceased:true
  shape spouse2 as @pedigree-female label:"Wife 2"

  # Children from first marriage
  shape child1 as @pedigree-male label:"Child 1"
  shape child2 as @pedigree-female label:"Child 2"

  # Children from second marriage
  shape child3 as @pedigree-male label:"Child 3"

  # Marriage relationships
  person -> spouse1 arrowType:none
  person -> spouse2 arrowType:none

  # First marriage children
  person -> child1
  person -> child2
  spouse1 -> child1
  spouse1 -> child2

  # Second marriage children
  person -> child3
  spouse2 -> child3
}

Notes:

• Children 1 and 2 are half-siblings to Child 3
• Wife 1 is marked deceased with diagonal line
• Both marriage lines shown without arrows

Unknown Sex Individual

When sex is unknown or not yet determined:

diagram "Unknown Sex" {
  direction:TB

  # Parents
  shape parent1 as @pedigree-male label:"Parent 1"
  shape parent2 as @pedigree-female label:"Parent 2"

  # Unborn or sex unknown child
  shape fetus as @pedigree-unknown label:"Fetus"

  # Marriage
  parent1 -> parent2 arrowType:none

  # Parent-child
  parent1 -> fetus
  parent2 -> fetus
}

Diamond Symbol: The @pedigree-unknown shape renders as a diamond, used for:

• Unborn children (prenatal testing)
• Miscarriages where sex unknown
• Historical records where sex not recorded

Combining Properties

All pedigree properties can be combined:

diagram "Combined Properties" {
  direction:TB

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

  # Deceased carrier
  shape grandmother as @pedigree-female label:"Grandmother" carrier:true deceased:true

  # Normal living individual (default)
  shape child as @pedigree-female label:"Child"
}

Rendering:

• Patient: Black-filled square with diagonal line
• Grandmother: Half-filled circle with diagonal line
• Child: White-filled circle (normal)

Best Practices

Generation Labels

Use Roman numerals for clarity:

shape i1 as @pedigree-male label:"I-1"     # Generation I, individual 1
shape ii3 as @pedigree-female label:"II-3" # Generation II, individual 3

ID Naming

Keep IDs simple and lowercase:

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

# Avoid hyphens in IDs
shape i-1 as @pedigree-male  # DON'T

Edge Order

Define marriages before parent-child relationships:

# 1. Marriages first
father -> mother arrowType:none

# 2. Then parent-child
father -> child
mother -> child

Direction

Always use top-to-bottom for pedigree charts:

diagram "My Pedigree" {
  direction:TB  # Required for proper pedigree layout
  # ...
}

Legend/Key

While Runiq doesn't auto-generate legends, include explanatory comments:

# Pedigree Key:
# ■ (black fill) = Affected by condition
# ▦ (half fill) = Carrier (heterozygous)
# □ (white fill) = Unaffected (normal)
# ⌿ (diagonal line) = Deceased
# ═ (double line) = Consanguineous marriage

Medical Standards

Runiq's pedigree implementation follows standard medical genetics notation:

Symbol	Meaning	Runiq Syntax
□ (square)	Male	@pedigree-male
○ (circle)	Female	@pedigree-female
◇ (diamond)	Unknown sex	@pedigree-unknown
■ (filled)	Affected	affected:true
▦ (half-filled)	Carrier	carrier:true
⌿ (diagonal line)	Deceased	deceased:true
─ (horizontal, no arrow)	Marriage	arrowType:none
═ (double line)	Consanguinity	lineStyle:double arrowType:none

See Also

• Pedigree Charts Guide - Complete pedigree documentation
• Shape Reference - All available shapes
• Edge Properties - Edge styling options