Building a Three-Generation Family Health Pedigree You Can Actually Use

A family health pedigree is not a family tree with names. It is a structured diagram — or a structured list — that captures who was diagnosed with what, at what age, and how they are related to you. Three generations (grandparents, parents/siblings/self, children) is the standard scope for most clinical purposes. The exercise takes an evening; the resulting document is what every doctor for the rest of your life will ask for.

The five columns of a usable pedigree

• Column: Relationship · Example: Paternal grandfather
• Column: Name (optional) · Example: Ram Kumar
• Column: Alive? · Example: No, died 2015
• Column: Age at diagnosis / death · Example: Died 72, heart attack; had diabetes from ~50
• Column: Known conditions · Example: Type 2 diabetes, hypertension, myocardial infarction

Do this for every person in the three generations who is or was living. For unknown information, write 'unknown' — better than leaving blank, because a doctor reading it can then ask specifically.

The specific pedigree structure

Three generations means:

• Generation 1: your four grandparents (2 paternal, 2 maternal), and their siblings if you know about them.
• Generation 2: your parents, their siblings (your aunts and uncles), any half-siblings.
• Generation 3: yourself, your siblings, your first cousins if health information is available.
• Sometimes generation 4: your children.

The nine categories to note against each person

Not because the person had them, but because these are the categories a doctor will ask about:

• Heart disease (heart attack, angina, bypass surgery, heart failure) — with age of onset.
• Stroke — with age.
• Diabetes — with age of onset, type if known, whether on insulin.
• High blood pressure — from what age.
• Cancer — which type, at what age, was there recurrence, treatment received.
• Kidney disease — dialysis, transplant, chronic condition.
• Mental illness — depression, anxiety, bipolar, schizophrenia, dementia.
• Genetic or hereditary conditions if known — thalassaemia, sickle cell, Duchenne, Huntington's, etc.
• Any unexplained early death — cause unknown but died young.

The visual pedigree — worth doing for complex families

For families with multiple affected relatives across generations, a visual pedigree diagram makes patterns visible that a list cannot. Standard conventions:

• Squares for males, circles for females.
• Filled shape = affected with the condition being tracked.
• Horizontal line between two shapes = mating pair.
• Vertical line down = children.
• Diagonal line through shape = deceased.

Any genetic counsellor uses these conventions. If a formal family history assessment is ever needed, a well-drawn pedigree saves an hour of interview.

Where to store it, and when to update

Your family health record app is the right place. Two update triggers:

• Any time a relative is diagnosed with a significant condition.
• Any time you sit with older relatives and learn something new about the previous generation.

A pedigree done once and never updated becomes stale. The habit of updating it at the same time as the annual family gathering — when older relatives are together and stories come up — is what keeps it useful.

References

• CDC — Family Health History
• US Surgeon General — My Family Health Portrait
• National Society of Genetic Counselors — pedigree standards