What 100 Simulated Offspring Actually Means

One of the more unusual things in a Genomisaur family report is offspring simulation. Instead of giving you a single guess about what traits your children might have, we simulate 100 possible children and show you the distribution. The reasoning is below, along with how the simulation actually works.

How Reproduction Works (Genetically)

Every child inherits roughly half their DNA from each parent. Which half is not the same every time. During the formation of egg and sperm cells, a process called recombination shuffles each parent's DNA, creating a unique combination for each reproductive cell. This is why siblings — who share the same parents — can be so different.

On top of recombination, which of the two copies of each chromosome a parent passes on is random (independent assortment). Each child receives a unique hand of cards dealt from both parents.

Why We Simulate 100 Children

Because inheritance is probabilistic, a single prediction ("your child will have brown eyes") is misleading. The reality is closer to "your children have a 60% chance of brown, 30% green, and 10% blue." The only way to capture that distribution is to simulate many possible outcomes.

Our pipeline takes both parents' genetic data and simulates the process of recombination and independent assortment 100 times, creating 100 hypothetical offspring genomes. Each simulated child has a complete genotype that we can analyze just like a real person's DNA.

We then calculate trait predictions and health risk scores for all 100 simulated children, giving you a distribution of outcomes rather than a single guess.

How to Read the Distribution Charts

For each trait and health condition in your family report, you'll see a distribution showing the range of outcomes across all 100 simulated offspring.

For categorical traits like eye color, the chart is a bar chart showing how many of the 100 simulated children are predicted to have each color. If 62 out of 100 simulated children have brown eyes, that's roughly a 62% probability.

For continuous traits like height, you'll see a histogram showing the spread of predicted values. The range tells you the realistic boundaries; the peak tells you the most likely outcome.

For health risk scores, the chart shows how the PRS percentiles distribute across simulated offspring. Some children may inherit higher predisposition than others for the same condition, and the distribution makes that range visible.

What the Simulation Can and Can't Tell You

The simulation models genetic inheritance accurately — how DNA is shuffled and passed down. It works well for traits that are primarily determined by common genetic variants (eye color, hair color, many health risk scores).

It has limits. Environmental factors aren't modeled, so a child's actual height also depends on nutrition and health during childhood. Rare de novo mutations (new mutations that arise spontaneously) aren't captured either, since we work from the parents' existing variants.

The simulation shows you the genetic possibilities. How those possibilities play out also depends on life experience.

Why This Matters for Family Planning

Seeing a distribution of outcomes is more honest, and more useful, than a single prediction. It lets you and your partner have informed conversations about what your future children might inherit, particularly when combined with carrier screening. If both parents are carriers for a recessive condition, the simulation shows exactly how that plays out across 100 possible children.