Genogram Symbols Explained

A genogram looks complicated at first glance, but it follows a consistent set of symbols that anyone can learn in a few minutes. Once you know the symbols, you can read any genogram and draw your own.

What is a genogram?

A genogram is a diagram that maps family relationships across generations — similar to a family tree, but richer. Where a family tree typically shows who is related to whom, a genogram also shows the nature of relationships, health history, and repeating patterns across generations. A genogram can capture whether a marriage ended in divorce, whether a family member was adopted, whether there is a history of a particular illness, or whether estrangement exists between relatives.

Genograms are widely used in medicine, psychology, social work, and family therapy. A doctor might use one to track hereditary conditions across three generations. A therapist might use one to identify recurring behavioural patterns. But genograms are equally useful for anyone researching their family history in depth — they hold far more information than a standard family tree diagram because the symbols do the work of describing relationships rather than leaving everything in written notes.

The key to reading and drawing genograms is understanding the standardised symbol set. Learn those, and the diagram becomes straightforward.

Person symbols

Each person in a genogram is represented by a shape. The shape itself communicates the person's gender or status, so you can read the diagram without needing labels for every characteristic.

• Square — represents a male family member
• Circle — represents a female family member
• Triangle — represents a pregnancy, miscarriage, or stillbirth (context or a brief label clarifies which)
• Filled or shaded square or circle — indicates a deceased individual; the shape is coloured in or heavily shaded
• Square or circle with an X through it — also used to indicate deceased, depending on the convention the creator is following
• Dotted outline square or circle — represents an adopted individual
• Half-filled symbol — used to indicate a serious illness or significant medical condition; the convention for which half is filled may vary
• Diamond or small unlabelled square — sometimes used for a person of unknown gender

Names, dates of birth, dates of death, and brief notes are typically written inside or directly beside each symbol. Keep notes short on the diagram itself — detailed records belong in supporting documents.

Relationship line symbols

Relationship lines are drawn horizontally between two people at the same generational level. The style of the line communicates the nature of their relationship. These are among the most important symbols to know, because they transform a genogram from a list of relatives into an actual picture of family dynamics.

• Single solid horizontal line — married couple
• Double solid horizontal line — common-law or de facto relationship
• Dashed horizontal line — separated couple
• Single line with two diagonal slashes through it — divorced couple
• Dotted horizontal line — distant or estranged relationship
• Wavy line — conflicted or hostile relationship

When a person has had multiple relationships, each is drawn separately. A person may have a divorced line to one partner and a marriage line to a current partner, for example. Each relationship line connects to the same person symbol, showing the sequence of relationships without needing to repeat the individual's symbol.

Parent-child lines

Children are shown below their parents, connected by vertical and diagonal lines. A vertical line drops from the midpoint of the couple's horizontal relationship line. Where a couple has multiple children, a horizontal bar extends across the bottom of that vertical line, and shorter diagonal lines drop from the bar to each child's symbol.

• Diagonal solid line to a child — biological child
• Dashed diagonal line to a child — adopted child
• Dotted diagonal line to a child — foster child

When a child belongs to only one of the two partners shown (for example, a child from a previous relationship who is now part of a blended family), the connecting line runs from the relevant biological or legal parent only. This keeps the diagram accurate without requiring long written explanations.

Twins

Twins are shown as two children connected at the same point on the horizontal bar above them. The way the lines meet indicates whether they are identical or fraternal twins.

• Identical twins — two lines that meet at a single shared point before branching down to each child; the lines form a narrow V shape meeting at the top
• Fraternal twins — two lines that branch separately from the horizontal bar at slightly different points, forming a wider shape without the lines meeting

This is a detail many genogram creators skip, but it is useful when tracking genetic conditions, because identical twins share the same DNA while fraternal twins do not.

How to draw a genogram — step by step

Drawing your first genogram is easier if you work outward from a single person rather than trying to map the entire family at once. Here is a simple sequence to follow:

1. Start with yourself at the centre of the page — a square if male, a circle if female. Write your name inside or beside the symbol.
2. Draw your parents above, with your father (square) on the left and your mother (circle) on the right. Connect them with a horizontal line using the correct relationship symbol — a single solid line if married, a double line if de facto, a slashed line if divorced.
3. Draw a vertical line from the midpoint of your parents' relationship line down to your own symbol to show the parent-child connection.
4. Add your siblings by drawing a horizontal bar across the bottom of that vertical line and connecting each sibling's symbol below it. Add biological lines for biological siblings, dashed lines for adopted siblings.
5. Continue upward for grandparents using the same pattern — a couple line, a vertical drop, children below.
6. Add any health notes, occupational details, or significant life events inside or beside each symbol, keeping them brief.
7. Include a legend in the corner of the diagram showing which symbols you have used and what they mean. This is important: even experienced readers may use slightly different conventions, and a legend removes ambiguity.

Work in pencil first if you are drawing by hand — genograms often need revision as you discover new details or realise you need more space for a particular branch.

Standard vs. custom symbols

There is no single universal standard for genogram symbols. Different professional fields — medicine, therapy, social work, academic research — use slightly different conventions, and various textbooks and training programmes have developed their own variations over the decades. The symbols described in this guide are the most widely used and recognised, but you may encounter alternatives.

The most common points of variation are: how deceased individuals are shown (filled shape vs. X), how adoptive relationships are drawn (dotted line vs. dashed), and whether additional symbols are used for specific health conditions or relationship types. When in doubt about a specific convention, check the legend on the genogram you are reading.

When sharing your own genogram with others — especially in a professional or medical context — always include a legend. This is good practice regardless of how standard your symbols are. It takes thirty seconds to add and prevents misinterpretation entirely.

The most widely referenced academic work on genogram standardisation is Monica McGoldrick's Genograms: Assessment and Intervention, available through most university libraries.

Frequently Asked Questions

What shape represents a male in a genogram?

A square represents a male family member in a genogram. A filled or shaded square indicates a deceased male.

What shape represents a female in a genogram?

A circle represents a female family member in a genogram. A filled or shaded circle indicates a deceased female.

What does a dashed line mean in a genogram?

A dashed horizontal line between two people in a genogram indicates a separated couple. A line with two diagonal slashes through it indicates a divorced couple.

What is the difference between a genogram and a family tree?

A family tree shows who is related to whom. A genogram uses standardised symbols to also show the nature of relationships — whether couples are married, separated, or divorced — as well as health history, adopted children, and family patterns across generations.